Coil Pack or Fuel Filter issue?

[old guy]

OK. Lets see what we can figure out. Your P1128 is a multiplicative code. That means your ECM is having to add fuel while the engine is under partial load. If it goes lean far enough and long enough that may be the cause of the limp mode. Since you now have VCDS it would be a good idea to look at your fuel trims to see how much fuel is being added.

You can get that information from measuring blocks 32 and 33. Here are two videos that are worth watching to help better explain fuel trims. Clicky click 1® and Clicky click 2®

The other thing you can do is to monitor your actual versus requested boost once you start to lose boost performance. You can use several of the Load Registration & Boost Pressure Control measuring blocks (110→119) to monitor this. Block 115 works well. If the ECM is calling for significantly more boost than your actual boost you need to look for a mechanical explanation. If the ECM is calling for reduced boost we will need to determine the conditions present that cause the ECM to reduce the boost. A chronic lean condition will definately cause it.

Here's a neat little chart to help you with utilizing the different measuring blocks available for diagnostic purposes. Clicky click 3®

[Prospect25]

OK. Lets see what we can figure out. Your P1128 is a multiplicative code. That means your ECM is having to add fuel while the engine is under partial load. If it goes lean far enough and long enough that may be the cause of the limp mode. Since you now have VCDS it would be a good idea to look at your fuel trims to see how much fuel is being added.

You can get that information from measuring blocks 32 and 33. Here are two videos that are worth watching to help better explain fuel trims. Clicky click 1® and Clicky click 2®

The other thing you can do is to monitor your actual versus requested boost once you start to lose boost performance. You can use several of the Load Registration & Boost Pressure Control measuring blocks (110→119) to monitor this. Block 115 works well. If the ECM is calling for significantly more boost than your actual boost you need to look for a mechanical explanation. If the ECM is calling for reduced boost we will need to determine the conditions present that cause the ECM to reduce the boost. A chronic lean condition will definately cause it.

Here's a neat little chart to help you with utilizing the different measuring blocks available for diagnostic purposes. Clicky click 3®

Thank you for the links to the videos; they were hugely helpful in understanding fuel trims and why they matter. The measuring block chart was also very helpful, although I think I confused myself by looking through all of them and trying to decipher what each of them means.

I was able to go out last night and drive on the highways both in the flat highways of Denver and up through the mountains. Usually the limp mode occurs after a drive up to the mountains from Denver, as it did all ski season and two weekends ago when i went mountain biking, hence my reason for trying to replicate the problem. I cleared all codes before i started and then I took some logs at cold startup as well as multiple pulls from third gear and one in 5th while headed up a long, steep hill. Here are the results, sorry if they're hard to read; i haven't figured out how to attach an excel file:



Tuesday 14 June 2016 20:11:08:02193
8E0 909 518 F 1.8L R4/5VT G 0004 Idling at Cold Startup

Group A: '032 Group B: '033 Group C: '115
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Engine Load Boost Pressure Boost Pressure
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (specified) (actual)
Marker STAMP % % STAMP % V STAMP /min % mbar mbar
0.16 0 0 0.34 0 1.52 0 1240 42.1 820 860
0.66 0 0 0.83 0 1.54 0.5 1240 42.1 820 860
1.17 0 0 1.35 0 1.52 0.99 1240 42.1 820 860
1.69 0 0 1.86 0 1.52 1.52 1240 41.4 820 860
2.2 0 0 2.38 0 1.54 2.03 1200 42.1 820 860
2.7 0 0 2.88 0 1.54 2.54 1240 41.4 820 860
3.23 0 0 3.39 0 1.54 3.05 1240 40.6 820 860
3.72 0 0 3.88 0 1.52 3.55 1200 40.6 820 860
4.22 0 0 4.39 0 1.52 4.06 1240 41.4 820 860
4.75 0 0 4.91 0 1.52 4.56 1240 40.6 820 860
5.25 0 0 5.41 0 1.54 5.09 1200 40.6 820 860
5.74 0 0 5.92 0 1.54 5.57 1200 41.4 820 860
6.26 0 0 6.43 0 1.52 6.09 1240 41.4 820 860
6.77 0 0 6.94 0 1.52 6.6 1240 40.6 820 860
7.27 0 0 7.44 0 1.54 7.11 1240 40.6 820 860
7.78 0 0 7.96 0 1.52 7.61 1240 39.8 820 860
8.3 0 0 8.46 0 1.52 8.13 1200 41.4 820 860
8.8 0 0 8.98 0 1.52 8.63 1240 40.6 820 860
9.32 0 0 9.49 0 1.52 9.15 1240 39.8 820 860
9.85 0 0 10.02 0 1.54 9.66 1240 40.6 820 860
10.36 0 0 10.53 0 1.52 10.19 1200 40.6 820 860
10.88 0 0 11.05 0 1.54 10.7 1240 39.8 820 860
11.39 0 0 11.57 0 1.52 11.22 1240 39.8 820 860
11.91 0 0 12.09 0 1.54 11.74 1240 39.8 820 860
12.42 0 0 12.59 0 1.52 12.25 1240 39.8 820 860
12.94 0 0 13.11 0 1.54 12.77 1240 39.1 820 860
13.43 0 0 13.61 0 1.54 13.27 1240 39.8 820 860
13.96 0 0 14.12 0 1.52 13.78 1240 39.1 820 860
14.46 0 0 14.62 0 1.52 14.29 1240 39.1 820 860
14.98 0 0 15.14 0 1.54 14.79 1240 39.1 820 860
15.47 0 0 15.64 0 1.52 15.31 1240 39.1 820 860
15.98 0 0 16.14 0 1.52 15.8 1240 39.1 820 850
16.47 0 0 16.64 0 1.52 16.3 1200 39.1 820 850
17 0 0 17.16 0 1.52 16.82 1240 39.1 820 850
17.49 0 0 17.66 0 1.52 17.32 1240 39.1 820 860
18.01 0 0 18.18 0 1.54 17.84 1240 39.1 820 850
18.52 0 0 18.7 0 1.54 18.35 1240 39.1 820 850
19.04 0 0 19.21 0 1.54 18.87 1240 39.1 820 850
19.55 0 0 19.73 0 1.52 19.38 1240 39.1 820 850
20.07 0 0 20.24 0 1.52 19.9 1240 38.3 820 860
20.59 0 0 20.76 0 1.52 20.42 1240 39.1 820 860
21.09 0 0 21.26 0 1.54 20.92 1240 38.3 820 850
21.6 0 0 21.76 0 1.52 21.42 1240 39.1 820 850
22.1 0 0 22.28 0 1.52 21.93 1240 39.1 820 860
22.62 0 0 22.79 0 1.52 22.44 1200 39.1 820 860


Tuesday 14 June 2016 20:12:04:02193-VCID:336566E5513DF9A6B3
8E0 909 518 F 1.8L R4/5VT G 0004 Still Idling at Startup - Jumps in Fuel Trim

Group A: '032 Group B: '033 Group C: '115
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Engine Load Boost Pressure Boost Pressure
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (specified) (actual)
Marker STAMP % % STAMP % V STAMP /min % mbar mbar
0.16 0 0 0.33 14.8 1.52 0 1240 24.8 820 820
0.67 0 0 0.84 14.8 1.56 0.5 1240 24.1 820 830
1.19 0 0 1.36 21.1 1.58 1.01 1240 24.1 820 830
1.69 0 0 1.86 21.1 1.56 1.53 1240 24.1 820 830
2.18 0 0 2.36 21.1 1.54 2.02 1240 24.1 820 830
2.68 0 0 2.84 16.4 1.54 2.52 1240 24.1 820 830
3.18 0 0 3.36 15.6 1.48 3.01 1240 24.1 820 830
3.7 0 0 3.87 16.4 1.54 3.52 1240 24.1 820 830
4.21 0 0 4.38 21.9 1.56 4.04 1240 24.1 820 830
4.73 0 0 4.9 21.1 1.54 4.55 1240 24.1 820 820
5.25 0 0 5.41 21.9 1.54 5.07 1240 24.1 820 820
5.76 0 0 5.93 16.4 1.54 5.58 1240 24.1 820 830
6.27 0 0 6.44 16.4 1.52 6.1 1240 24.1 820 820
6.79 0 0 6.96 16.4 1.52 6.62 1200 24.1 820 830
7.31 0 0 7.48 16.4 1.56 7.13 1240 23.3 820 830
7.82 0 0 8 21.9 1.56 7.65 1240 23.3 820 820
8.34 0 0 8.51 22.7 1.56 8.17 1240 24.1 820 820
8.84 0 0 9.01 22.7 1.56 8.67 1240 24.1 820 830
9.35 0 0 9.52 17.2 1.5 9.18 1240 24.1 820 820
9.86 0 0 10.03 17.2 1.5 9.68 1240 24.1 820 830
10.38 0 0 10.55 14.1 1.2 10.21 1240 18.8 820 830
10.87 0 0 11.04 14.1 1.3 10.71 1240 20.3 820 820
11.38 0 0 11.56 11.7 1.32 11.21 1200 19.5 820 820
11.9 0 0 12.07 9.4 1.32 11.73 1160 18.8 820 820
12.41 0 0 12.57 2.3 1.36 12.25 1160 18 820 820
12.91 0 0 13.08 1.6 1.42 12.74 1120 18.8 820 820
13.43 0 0 13.59 0 1.46 13.26 1080 18 820 820
13.93 0 0 14.11 5.5 1.56 13.76 1040 18.8 820 820
14.44 0 0 14.6 7 1.6 14.28 1040 18.8 820 820
14.94 0 0 15.1 8.6 1.62 14.77 1040 18.8 820 820
15.43 0 0 15.58 4.7 1.6 15.27 1000 19.5 820 820
15.92 0 0 16.09 5.5 1.58 15.75 960 18.8 820 820
16.41 0 0 16.58 5.5 1.58 16.25 960 18.8 820 820
16.92 0 0 17.09 10.9 1.54 16.74 920 18.8 820 820
17.43 0 0 17.6 10.2 1.5 17.26 880 18 820 820
17.93 0 0 18.11 10.2 1.52 17.76 880 18.8 820 820
18.43 0 0 18.61 4.7 1.54 18.27 840 18.8 820 820
18.95 0 0 19.13 5.5 1.56 18.78 800 18.8 820 820
19.46 0 0 19.63 5.5 1.56 19.29 800 19.5 820 820
19.98 0 0 20.16 6.3 1.56 19.8 760 18.8 820 820
20.49 0 0 20.65 11.7 1.56 20.33 760 19.5 820 820
21 0 0 21.17 11.7 1.58 20.82 760 19.5 820 820
21.49 0 0 21.66 12.5 1.58 21.33 760 19.5 820 820
22.02 0 0 22.17 7.8 1.58 21.83 760 19.5 820 820
22.52 0 0 22.69 7.8 1.56 22.35 760 19.5 820 820
23.04 0 0 23.21 7.8 1.56 22.87 760 19.5 820 820
23.55 0 0 23.72 13.3 1.54 23.38 760 19.5 820 820
24.05 0 0 24.22 13.3 1.54 23.89 760 19.5 820 820
24.56 0 0 24.72 13.3 1.52 24.39 760 19.5 820 820
25.07 0 0 25.23 7.8 1.54 24.89 760 19.5 820 820
25.56 0 0 25.74 8.6 1.56 25.4 760 19.5 820 820
26.09 0 0 26.25 8.6 1.56 25.91 760 19.5 820 820
26.6 0 0 26.77 14.1 1.56 26.42 760 19.5 820 820
27.11 0 0 27.28 14.1 1.56 26.94 760 19.5 820 820
27.63 0 0 27.8 14.1 1.56 27.46 760 20.3 820 820
28.13 0 0 28.3 14.1 1.56 27.97 760 20.3 820 820
28.64 0 0 28.81 9.4 1.56 28.47 760 20.3 820 820
29.17 0 0 29.33 9.4 1.56 28.99 760 20.3 820 820
29.66 0 0 29.83 9.4 1.56 29.49 760 20.3 820 820





I noticed the fuel trim start jumping up way past +- 10% so took the log. This was still while it was idling and when the revs dropped from about 1240 RPM to 760.

This next grouping is of the third gear pulls, one fifth gear pull, and then idling after driving to cool down.


Tuesday 14 June 2016 20:25:11:02193-VCID:336566E5513DF9A6B3
8E0 909 518 F 1.8L R4/5VT G 0004 3rd Gear Pull once engine was sufficiently warm

Group A: '032 Group B: '033 Group C: '115
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Engine Load Boost Pressure Boost Pressure
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (specified) (actual)
Marker STAMP % % STAMP % V STAMP /min % mbar mbar
0.33 -0.2 18 0 -2.3 1.66 0.17 2080 14.3 820 880
0.85 -0.2 18 0.5 0 3.1 0.67 2160 47.4 1240 850
1.36 -0.2 18 1.02 0 1.38 1.2 2080 66.9 1790 950
1.85 -0.2 18 1.52 2.3 1.3 1.68 2160 75.9 1820 1070
2.36 -0.2 18 2.02 3.9 1.22 2.19 2280 86.5 1890 1210
2.88 -0.2 18 2.53 3.9 1.16 2.71 2440 97.7 2030 1350
3.39 -0.2 18 3.04 3.9 1.08 3.22 2600 111.3 2110 1520
3.9 -0.2 18 3.56 3.9 1.12 3.73 2760 128.6 2210 1740
4.43 -0.2 18 4.08 3.1 0.98 4.25 2920 154.9 2350 2030
4.94 -0.2 18 4.6 -2.3 1.06 4.77 3120 173.7 2370 2240
5.44 -0.2 18 5.12 -0.8 1.08 5.28 3320 179.7 2350 2300
5.95 -0.2 18 5.61 1.6 1.02 5.78 3520 178.2 2330 2240
6.48 -0.2 18 6.14 0.8 0.9 6.32 3720 173.7 2320 2200
6.97 -0.2 18 6.64 -2.3 1 6.81 3880 167.7 2310 2180
7.48 -0.2 18 7.15 -1.6 0.98 7.31 4080 163.2 2280 2150
7.99 -0.2 18 7.65 -3.9 0.88 7.82 4280 159.4 2220 2080
8.49 -0.2 18 8.15 -5.5 0.92 8.32 4440 154.1 2160 2000
9 -0.2 18 8.66 -7.8 0.88 8.83 4600 148.9 2120 1960
9.51 -0.2 18 9.17 -7 0.84 9.35 4760 146.6 2080 1880
10.02 -0.2 18 9.67 -6.3 0.5 9.85 4880 142.9 2030 1840
10.53 -0.2 18 10.19 -4.7 0.3 10.36 5040 138.3 1990 1800
11.04 -0.2 18 10.7 -3.9 0.04 10.87 5160 135.3 1950 1760
11.57 -0.2 18 11.21 -3.1 0.02 11.4 5240 133.1 1890 1710
12.08 -0.2 18 11.74 -2.3 0.02 11.91 5360 130.1 1850 1690
12.58 -0.2 18 12.25 -2.3 0.02 12.42 5480 127.1 1790 1650
13.07 -0.2 18 12.74 -1.6 0.06 12.9 5600 125.6 1770 1620
13.6 -0.2 18 13.26 -1.6 0.1 13.43 5720 122.6 1750 1610
14.11 -0.2 18 13.77 -0.8 0.14 13.94 5800 121.1 1730 1580
14.61 -0.2 18 14.27 -0.8 0.14 14.45 5920 117.3 1720 1580
15.13 -0.2 18 14.78 -0.8 0.12 14.96 6000 117.3 1710 1540
15.63 -0.2 18 15.31 -0.8 0.02 15.47 6120 115.8 1690 1530


Tuesday 14 June 2016 20:35:49:02193-VCID:336566E5513DF9A6B3
8E0 909 518 F 1.8L R4/5VT G 0004 5th Gear Pull up Long Hill

Group A: '032 Group B: '033 Group C: '115
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Engine Load Boost Pressure Boost Pressure
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (specified) (actual)
Marker STAMP % % STAMP % V STAMP /min % mbar mbar
0 -0.2 20.3 0.17 5.5 1.48 0.33 3000 98.5 2300 1290
0.5 -0.2 20.3 0.67 0.8 1.26 0.85 2960 133.1 2320 1770
1.01 -0.2 20.3 1.18 -3.9 1.2 1.36 3000 162.4 2350 2140
1.53 -0.2 20.3 1.71 -3.9 1.3 1.88 3000 172.9 2340 2280
2.05 -0.2 20.3 2.22 -3.1 1.18 2.39 3040 176.7 2340 2310
2.57 -0.2 20.3 2.73 -3.1 1.18 2.9 3080 176.7 2340 2320
3.07 -0.2 20.3 3.24 -2.3 1.18 3.41 3080 175.9 2330 2310
3.58 -0.2 20.3 3.75 -3.1 1.12 3.93 3120 175.9 2310 2300
4.09 -0.2 20.3 4.26 -3.1 1.1 4.43 3160 175.2 2310 2290
4.6 -0.2 20.3 4.77 -2.3 1.1 4.95 3160 178.2 2300 2320
5.12 -0.2 20.3 5.29 -2.3 1.04 5.44 3200 178.2 2290 2350
5.6 -0.2 20.3 5.77 -1.6 1.02 5.95 3240 176.7 2290 2320
6.11 -0.2 20.3 6.28 -2.3 1.04 6.45 3280 172.2 2280 2300
6.62 -0.2 20.3 6.79 -2.3 1.02 6.97 3280 170.7 2270 2260
7.13 -0.2 20.3 7.29 -3.1 0.94 7.46 3320 168.4 2260 2250
7.63 -0.2 20.3 7.8 -1.6 0.52 7.99 3320 166.9 2250 2220
8.15 -0.2 20.3 8.31 -1.6 0.46 8.48 3360 166.2 2250 2200
8.65 -0.2 20.3 8.82 -1.6 0.34 8.99 3400 164.7 2230 2180
9.16 -0.2 20.3 9.33 -0.8 0.26 9.5 3400 164.7 2230 2160
9.68 -0.2 20.3 9.84 -0.8 0.32 10.02 3440 163.9 2230 2150
10.19 -0.2 20.3 10.35 -0.8 0.3 10.51 3480 162.4 2220 2160
10.68 -0.2 20.3 10.84 -0.8 0.34 11.01 3480 162.4 2220 2160
11.18 -0.2 20.3 11.35 -0.8 0.3 11.52 3480 161.7 2210 2160
11.69 -0.2 20.3 11.86 -0.8 0.3 12.03 3520 161.7 2210 2120
12.2 -0.2 20.3 12.36 -0.8 0.3 12.54 3560 160.2 2200 2130
12.71 -0.2 20.3 12.88 -0.8 0.3 13.05 3600 160.2 2200 2110
13.23 -0.2 20.3 13.41 -0.8 0.28 13.58 3600 158.6 2180 2110
13.75 -0.2 20.3 13.92 -0.8 0.34 14.09 3640 159.4 2170 2100
14.26 -0.2 20.3 14.43 -0.8 0.28 14.6 3640 157.9 2160 2100
14.77 -0.2 20.3 14.95 -0.8 0.28 15.11 3680 157.9 2160 2100
15.28 -0.2 20.3 15.45 -0.8 0.22 15.62 3680 157.1 2140 2100
15.79 -0.2 20.3 15.96 -0.8 0.22 16.13 3720 157.9 2130 2110
16.3 -0.2 20.3 16.48 -0.8 0.12 16.65 3720 157.9 2130 2110
16.81 -0.2 20.3 16.98 -0.8 0.24 17.15 3760 156.4 2120 2130
17.32 -0.2 20.3 17.5 -0.8 0.2 17.66 3760 157.1 2110 2120
17.83 -0.2 20.3 18 -0.8 0.16 18.16 3760 157.1 2090 2100


Tuesday 14 June 2016 20:51:23:02193-VCID:336566E5513DF9A6B3-515E VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004 3rd Gear Pull about 30 Minutes into Drive

Group A: '032 Group B: '033 Group C: '115
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Engine Load Boost Pressure Boost Pressure
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (specified) (actual)
Marker STAMP % % STAMP % V STAMP /min % mbar mbar
0.17 -0.2 19.5 0.35 0 2.16 0 1160 18.8 760 790
0.67 -0.2 19.5 0.84 0 1.08 0.51 1720 56.4 1810 780
1.18 -0.2 19.5 1.35 -1.6 1.26 1.01 1920 60.9 1850 860
1.68 -0.2 19.5 1.85 2.3 1.18 1.51 2040 69.2 1900 970
2.18 -0.2 19.5 2.36 3.9 1.1 2.01 2160 76.7 1930 1070
2.69 -0.2 19.5 2.87 5.5 1.08 2.52 2280 85 2000 1190
3.21 -0.2 19.5 3.38 4.7 1.02 3.04 2440 97 2110 1320
3.72 -0.2 19.5 3.89 4.7 1.06 3.55 2600 111.3 2210 1490
4.23 -0.2 19.5 4.41 3.1 0.82 4.06 2760 128.6 2290 1720
4.74 -0.2 19.5 4.91 -3.1 1 4.58 2920 155.6 2340 2020
5.25 -0.2 19.5 5.42 -1.6 1.02 5.08 3120 169.2 2340 2160
5.76 -0.2 19.5 5.93 0 0.94 5.59 3320 173.7 2340 2180
6.27 -0.2 19.5 6.44 0 0.9 6.1 3520 169.2 2330 2110
6.78 -0.2 19.5 6.95 -2.3 0.92 6.61 3680 164.7 2330 2080
7.3 -0.2 19.5 7.46 -1.6 1 7.12 3840 158.6 2300 2080
7.79 -0.2 19.5 7.97 -1.6 0.94 7.63 4040 154.9 2270 2010
8.31 -0.2 19.5 8.47 -2.3 0.86 8.13 4200 149.6 2200 1980
8.81 -0.2 19.5 8.97 -5.5 0.84 8.64 4400 145.9 2130 1910
9.31 -0.2 19.5 9.47 -7.8 0.92 9.13 4520 141.4 2070 1840
9.81 -0.2 19.5 9.98 -7 0.76 9.63 4680 138.3 2020 1790
10.32 -0.2 19.5 10.49 -6.3 0.56 10.15 4840 133.8 1980 1740
10.83 -0.2 19.5 11.01 -7 0.56 10.66 5000 130.8 1940 1680
11.33 -0.2 19.5 11.51 -5.5 0.6 11.17 5120 127.1 1880 1670
11.85 -0.2 19.5 12.02 -4.7 0.6 11.68 5240 124.8 1840 1620
12.37 -0.2 19.5 12.54 -3.9 0.6 12.19 5360 121.8 1800 1580
12.88 -0.2 19.5 13.05 -3.9 0.62 12.7 5480 119.5 1750 1540
13.4 -0.2 19.5 13.57 -3.9 0.58 13.23 5600 118 1730 1500
13.91 -0.2 19.5 14.08 -3.9 0.54 13.74 5720 116.5 1710 1490
14.42 -0.2 19.5 14.6 -3.9 0.54 14.25 5800 113.5 1690 1480
14.94 -0.2 19.5 15.12 -3.1 0.44 14.75 5920 111.3 1690 1480


Tuesday 14 June 2016 21:04:47:02193-VCID:336566E5513DF9A6B3
8E0 909 518 F 1.8L R4/5VT G 0004 Another 3rd Gear Pull I Started Logging Late

Group A: '032 Group B: '033 Group C: '115
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Engine Load Boost Pressure Boost Pressure
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (specified) (actual)
Marker STAMP % % STAMP % V STAMP /min % mbar mbar
4.53 -0.4 18.8 4.71 4.7 0.92 4.37 2560 109.8 2130 1490
5.05 -0.4 18.8 5.22 3.9 0.88 4.88 2680 122.6 2140 1660
5.57 -0.4 18.8 5.74 -2.3 0.78 5.4 2840 142.9 2180 1910
6.08 -0.4 18.8 6.26 -2.3 0.98 5.91 3040 160.2 2190 2110
6.6 -0.4 18.8 6.76 -2.3 0.98 6.44 3200 166.9 2190 2140
7.09 -0.4 18.8 7.26 -1.6 0.92 6.93 3400 166.9 2190 2110
7.61 -0.4 18.8 7.77 -1.6 0.92 7.44 3560 162.4 2180 2070
8.11 -0.4 18.8 8.28 -3.1 0.9 7.94 3720 159.4 2180 2050
8.63 -0.4 18.8 8.79 -2.3 0.92 8.45 3880 154.9 2190 2010
9.13 -0.4 18.8 9.3 -3.1 0.86 8.96 4080 148.1 2170 1970
9.65 -0.4 18.8 9.81 -7 0.86 9.47 4280 143.6 2180 1900
10.16 -0.4 18.8 10.33 -10.2 0.82 9.99 4440 139.1 2090 1820
10.66 -0.4 18.8 10.83 -7.8 0.7 10.5 4640 134.6 2040 1760
11.17 -0.4 18.8 11.34 -7 0.56 11 4800 129.3 1990 1690
11.69 -0.4 18.8 11.85 -6.3 0.6 11.53 5000 124.1 1930 1640
12.19 -0.4 18.8 12.36 -5.5 0.64 12.02 5120 122.6 1870 1590
12.7 -0.4 18.8 12.87 -3.9 0.62 12.54 5280 118 1810 1560
13.2 -0.4 18.8 13.38 0 0.4 13.04 5440 115 1730 1530


Tuesday 14 June 2016 21:50:12:02193-VCID:336566E5513DF9A6B3
8E0 909 518 F 1.8L R4/5VT G 0004 Idling - Cool Down after Drive

Group A: '032 Group B: '033 Group C: '115
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Engine Load Boost Pressure Boost Pressure
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (specified) (actual)
Marker STAMP % % STAMP % V STAMP /min % mbar mbar
0 -0.4 19.5 0.17 0.8 1.52 0.34 760 17.3 820 820
0.51 -0.4 19.5 0.68 6.3 1.54 0.84 760 17.3 820 820
1.02 -0.4 19.5 1.19 6.3 1.52 1.36 760 17.3 820 820
1.54 -0.4 19.5 1.71 6.3 1.52 1.88 760 17.3 820 820
2.05 -0.4 19.5 2.22 0.8 1.5 2.38 760 17.3 820 820
2.56 -0.4 19.5 2.72 0.8 1.54 2.9 760 17.3 820 820
3.06 -0.4 19.5 3.23 1.6 1.54 3.4 760 17.3 820 820
3.57 -0.4 19.5 3.73 6.3 1.54 3.91 760 17.3 820 820
4.08 -0.4 19.5 4.25 7 1.54 4.43 760 17.3 820 820
4.59 -0.4 19.5 4.76 6.3 1.5 4.93 760 17.3 820 820
5.1 -0.4 19.5 5.27 6.3 1.5 5.44 760 17.3 820 820
5.62 -0.4 19.5 5.78 0.8 1.52 5.95 760 17.3 820 820
6.12 -0.4 19.5 6.29 0.8 1.54 6.46 760 17.3 820 820
6.63 -0.4 19.5 6.8 0.8 1.54 6.97 760 17.3 820 820
7.14 -0.4 19.5 7.31 6.3 1.52 7.49 760 17.3 820 820
7.66 -0.4 19.5 7.83 6.3 1.52 8.01 760 17.3 820 820
8.18 -0.4 19.5 8.35 6.3 1.5 8.52 760 17.3 820 820
8.7 -0.4 19.5 8.86 0.8 1.52 9.02 760 17.3 820 820
9.19 -0.4 19.5 9.36 0.8 1.52 9.54 760 17.3 820 820
9.7 -0.4 19.5 9.87 0.8 1.52 10.04 760 17.3 820 820
10.21 -0.4 19.5 10.38 5.5 1.54 10.56 760 17.3 820 820
10.73 -0.4 19.5 10.9 6.3 1.52 11.07 760 17.3 820 820
11.24 -0.4 19.5 11.42 6.3 1.52 11.6 760 17.3 820 820
11.77 -0.4 19.5 11.94 5.5 1.5 12.11 760 17.3 820 820
12.28 -0.4 19.5 12.45 0.8 1.5 12.63 760 17.3 820 820
12.79 -0.4 19.5 12.96 0 1.52 13.13 760 17.3 820 820
13.31 -0.4 19.5 13.48 0 1.52 13.66 760 17.3 820 820
13.82 -0.4 19.5 13.98 5.5 1.52 14.15 760 17.3 820 820
14.32 -0.4 19.5 14.49 5.5 1.52 14.67 760 17.3 820 820
14.83 -0.4 19.5 14.99 5.5 1.52 15.17 760 17.3 820 820
15.34 -0.4 19.5 15.51 0 1.52 15.68 760 17.3 820 820
15.84 -0.4 19.5 16.01 0 1.52 16.17 760 17.3 820 820
16.34 -0.4 19.5 16.5 0 1.52 16.67 760 17.3 820 820
16.85 -0.4 19.5 17.02 4.7 1.52 17.19 760 17.3 820 820
17.36 -0.4 19.5 17.53 4.7 1.52 17.71 760 17.3 820 820
17.88 -0.4 19.5 18.05 4.7 1.52 18.22 760 17.3 820 820
18.39 -0.4 19.5 18.57 4.7 1.52 18.75 760 17.3 820 820
18.91 -0.4 19.5 19.08 0 1.52 19.24 760 17.3 820 820
19.4 -0.4 19.5 19.57 0 1.52 19.74 760 17.3 820 820
19.91 -0.4 19.5 20.08 0 1.56 20.26 760 17.3 820 820
20.42 -0.4 19.5 20.59 4.7 1.54 20.76 760 17.3 820 820
20.93 -0.4 19.5 21.1 4.7 1.52 21.27 760 17.3 820 820
21.44 -0.4 19.5 21.62 4.7 1.52 21.79 760 17.3 820 820
21.97 -0.4 19.5 22.14 0 1.52 22.31 760 17.3 820 820
22.49 -0.4 19.5 22.65 -0.8 1.52 22.81 760 17.3 820 820
22.97 -0.4 19.5 23.14 -0.8 1.54 23.31 760 17.3 820 820
23.49 -0.4 19.5 23.65 4.7 1.52 23.82 760 17.3 820 820
23.99 -0.4 19.5 24.16 4.7 1.52 24.32 760 17.3 820 820

After i turned the car off, I turned the power back on to check for any fault codes. The only one there was P0411 for the SAI. Additionally, the car boosted fine the whole drive and did not kick into limp mode once. Maybe it knows i'm posting the data and it wants to make a liar out of me

So, what can i interpret from the data? Should i run some more logs on different measuring blocks? Do i wait for the CEL to come back on and try to replicate the problem again? Not sure how to make sense of it all.

Thanks for your help!
AJ

[old guy]

IDLING AT COLD START UP
This log really doesn’t show you much. Once you reset all codes the fuel trims go to zero. During a cold start your fuel control is in open loop so there are no fuel trims being adjusted. That is why your idle, partial and short term fuel trims are all at zero. Once you get out of the open loop condition the fuel trims will start to adjust to the prevailing conditions. You can tell that you are at an altitude of a little over 5,000 feet because of your 820 mbar boost pressure reading. At sea level it is typically around 1,000 mbar.

STILL IDLING AT START-UP. JUMPS IN FUEL TRIM
In this log you are going into a closed loop condition. While you were still at fast idle the STFT went as high as ~23%. That could be an indication of some false (non-metered) air entering somewhere. Once the idle dropped to normal the STFT reduced somewhat but still stayed pretty high.

THIRD GEAR PUILL ONCE ENGINE WAS SUFFICIENTLY WARM
In this log as well as the subsequent logs you can see that there are some rather serious fuel trim adjustments being made. In the third gear log the partial adaptation is up to 18%. In the FITH GEAR LOG the partial adaptation is up to 20.3%. In the LATE THIRD GEAR LOG as well as the IDLING COOL DOWN LOG your partial adaptation varies between 18.8 and 19.5%. The maximum adjustment the ECM can make is 25%.

I suspect that this is the cause of your intermittent limp mode. Once the adjustments get too high the ECM goes into limp mode to protect the engine. Now you need to figure out the cause for the high LTFT adjustments. A good place to start would be a boost pressure test. Look really close for any leaks between the MAF sensor and the turbo inlet. A rip or tear in the TIP would let the turbo suck in air that didn’t go through the MAF sensor and consequently the ECM would not be adding enough fuel for the actual air mass. Another possibility is a dirty or defective MAF sensor. If it isn’t reading the actual air mass the ECM won’t add enough fuel. The wideband O2 sensor lets the ECM know that “Hey! Things are getting a little lean in here!” and the fuel trims kick in to get everything back in check.

[Prospect25]

IDLING AT COLD START UP
This log really doesn’t show you much. Once you reset all codes the fuel trims go to zero. During a cold start your fuel control is in open loop so there are no fuel trims being adjusted. That is why your idle, partial and short term fuel trims are all at zero. Once you get out of the open loop condition the fuel trims will start to adjust to the prevailing conditions. You can tell that you are at an altitude of a little over 5,000 feet because of your 820 mbar boost pressure reading. At sea level it is typically around 1,000 mbar.

STILL IDLING AT START-UP. JUMPS IN FUEL TRIM
In this log you are going into a closed loop condition. While you were still at fast idle the STFT went as high as ~23%. That could be an indication of some false (non-metered) air entering somewhere. Once the idle dropped to normal the STFT reduced somewhat but still stayed pretty high.

THIRD GEAR PUILL ONCE ENGINE WAS SUFFICIENTLY WARM
In this log as well as the subsequent logs you can see that there are some rather serious fuel trim adjustments being made. In the third gear log the partial adaptation is up to 18%. In the FITH GEAR LOG the partial adaptation is up to 20.3%. In the LATE THIRD GEAR LOG as well as the IDLING COOL DOWN LOG your partial adaptation varies between 18.8 and 19.5%. The maximum adjustment the ECM can make is 25%.

I suspect that this is the cause of your intermittent limp mode. Once the adjustments get too high the ECM goes into limp mode to protect the engine. Now you need to figure out the cause for the high LTFT adjustments. A good place to start would be a boost pressure test. Look really close for any leaks between the MAF sensor and the turbo inlet. A rip or tear in the TIP would let the turbo suck in air that didn’t go through the MAF sensor and consequently the ECM would not be adding enough fuel for the actual air mass. Another possibility is a dirty or defective MAF sensor. If it isn’t reading the actual air mass the ECM won’t add enough fuel. The wideband O2 sensor lets the ECM know that “Hey! Things are getting a little lean in here!” and the fuel trims kick in to get everything back in check.

old guy - thank you for your time and interpreting my logs for me. After taking a few days to fully analyze the logs with the write up you provided it certainly makes much more sense! Hopefully we can leverage the data to make the most senses out of it and find the culprit of the underlying issue causing the fuel trim adjustments

To understand the jump in fuel trim when it goes from fast to slow idle, is this to warm the car and emissions system up faster, thus the reason for increase in fuel?

I recently did a boost pressure test and did not find any major leaks while charging the PVC pressure tester to about 25 psi. I have an APR silicone TIP with a stock MAF and did find there were some pin-sized holes in the TIP letting out small amounts of air that I was able to seal up. After sealing the TIP, i could not find any leaks in the system.

I did some research on testing for a bad MAF and found the following thread: clicky Post 15 in the thread detailed a way to remove the MAF and evaluate the g/s flow of the MAF to see if it was good or bad. I did some logs after i let the engine idle to a warm temp and did a few logs.

With the existing CEL codes of P0411 - 002 - Incorrect Flow Detected and P1128 - 001 - System too lean - Intermittent, I logged block 003 to see if the MAF was in normal operating readings as well as 032 and 033 again to monitor the long and short term fuel trims. Here are the results from that log (sorry again it's hard to read):

Monday 20 June 2016 20:27:54:02193-VCID:336566E5513DF9A6B3-5140 VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '003 Group B: '032 Group C: '033
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (G70) Timing Angle TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP % % STAMP % V
0.09 760 3.06 2.4 8.3 0.26 -0.4 19.5 0.44 3.1 1.54
0.61 760 3.06 2.4 6.8 0.78 -0.4 19.5 0.95 7.8 1.54
1.13 760 3.06 2.4 6.8 1.29 -0.4 19.5 1.45 7.8 1.54
1.62 760 3.06 2.4 7.5 1.78 -0.4 19.5 1.95 8.6 1.54
2.12 760 3.06 2.4 9 2.3 -0.4 19.5 2.48 8.6 1.54
2.64 760 3.06 2.4 7.5 2.81 -0.4 19.5 2.98 3.1 1.54
3.14 760 3.06 2.4 10.5 3.31 -0.4 19.5 3.48 3.1 1.56
3.65 760 3.08 2.4 8.3 3.84 -0.4 19.5 3.99 3.9 1.54
4.17 760 3.06 2.4 6.8 4.34 -0.4 19.5 4.51 8.6 1.54
4.68 760 3.08 2.4 6.8 4.84 -0.4 19.5 5.01 8.6 1.5
5.18 760 3.06 2.4 6.8 5.36 -0.4 19.5 5.53 7.8 1.52
5.7 760 3.03 2.4 9 5.88 -0.4 19.5 6.05 3.1 1.54
6.23 760 3.03 2.4 9.8 6.39 -0.4 19.5 6.55 3.1 1.54
6.72 760 3.03 2.4 9 6.89 -0.4 19.5 7.05 3.1 1.56
7.22 760 3.06 2.4 7.5 7.39 -0.4 19.5 7.57 8.6 1.54
7.74 760 3.06 2.4 7.5 7.92 -0.4 19.5 8.08 8.6 1.52
8.25 760 3.06 2.4 6.8 8.42 -0.4 19.5 8.58 8.6 1.52
8.75 760 3.06 2.4 7.5 8.92 -0.4 19.5 9.1 3.1 1.5
9.28 760 3.06 2.4 8.3 9.44 -0.4 19.5 9.61 2.3 1.52
9.78 760 3.08 2.4 9 9.96 -0.4 19.5 10.12 2.3 1.56
10.29 760 3.06 2.4 7.5 10.46 -0.4 19.5 10.63 3.1 1.56
10.79 760 3.06 2.4 6.8 10.96 -0.4 19.5 11.14 7.8 1.54
11.32 760 3.06 2.4 6.8 11.49 -0.4 19.5 11.67 7.8 1.52
11.83 760 3.06 2.4 6.8 11.99 -0.4 19.5 12.16 7.8 1.52
12.34 760 3.06 2.4 7.5 12.5 -0.4 19.5 12.67 2.3 1.54
12.84 760 3.06 2.4 9 13.02 -0.4 19.5 13.18 2.3 1.54
13.34 760 3.06 2.4 9 13.51 -0.4 19.5 13.68 3.1 1.56
13.85 760 3.06 2.4 6.8 14.02 -0.4 19.5 14.19 7.8 1.52


The numbers for the MAF seem good (between 2-5 g/s) and the fuel trims correlate to the CEL. I then turned the car off, cleared the codes and unplugged the MAF. Below is the log with the MAF unplugged:


Monday 20 June 2016 20:44:26:02193-VCID:336566E5513DF9A6B3-515E VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '003 Group B: '032 Group C: '033
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (G70) Timing Angle TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP % % STAMP % V
0.17 760 0 2.7 6.8 0.33 0 0 0 0 1.52
0.66 760 0 2.4 8.3 0.83 0 0 0.5 0 1.52
1.18 760 0 2.4 9 1.35 0 0 1.01 0 1.52
1.7 760 0 2.4 6.8 1.86 0 0 1.53 0 1.52
2.19 760 0 2.4 7.5 2.36 0 0 2.02 0 1.52
2.71 760 0 2.7 7.5 2.88 0 0 2.53 0 1.52
3.22 760 0 2.4 7.5 3.38 0 0 3.05 0 1.52
3.72 760 0 2.4 7.5 3.89 0 0 3.55 0 1.52
4.23 760 0 2.7 9 4.4 0 0 4.07 0 1.52
4.75 760 0 2.7 7.5 4.91 0 0 4.58 0 1.52
5.25 760 0 2.7 7.5 5.42 0 0 5.08 0 1.52
5.76 760 0 2.7 7.5 5.93 0 0 5.59 0 1.52
6.29 760 0 2.7 5.3 6.47 0 0 6.11 0 1.52
6.79 760 0 2.7 7.5 6.96 0 0 6.63 0 1.52
7.3 760 0 2.4 7.5 7.47 0 0 7.13 0 1.52
7.8 760 0 2.4 7.5 7.97 0 0 7.64 0 1.52
8.32 760 0 2.4 7.5 8.49 0 0 8.15 0 1.52
8.83 760 0 2.4 9 9 0 0 8.66 0 1.52
9.35 760 0 2.4 7.5 9.52 0 0 9.17 0 1.52
9.87 760 0 2.4 6.8 10.04 0 0 9.69 0 1.52
10.38 760 0 2.4 7.5 10.55 0 0 10.21 0 1.52
10.89 760 0 2.4 8.3 11.06 0 0 10.72 0 1.52
11.4 760 0 2.4 6 11.56 0 0 11.23 0 1.52
11.91 760 0 2.4 6.8 12.08 0 0 11.74 0 1.52
12.42 760 0 2.4 7.5 12.59 0 0 12.25 0 1.52
12.93 760 0 2.4 7.5 13.09 0 0 12.76 0 1.52
13.44 760 0 2.4 7.5 13.61 0 0 13.27 0 1.52

These numbers also seem to make sense to me. MAF unplugged = reading of 0. Since the codes were cleared the fuel trims are reset back to zero as well.

I then plugged the MAF back in and the log below is from that quick trip around the block in first gear:

Monday 20 June 2016 20:50:20:02193-VCID:336566E5513DF9A6B3-515E VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '003 Group B: '032 Group C: '033
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (G70) Timing Angle TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP % % STAMP % V
0.48 760 3.22 2.4 6 0.13 0 0 0.31 14.1 1.52
0.98 760 3.17 2.4 6.8 0.64 0 0 0.82 14.8 1.54
1.49 760 3.17 2.7 6 1.15 0 0 1.32 19.5 1.54
2 1200 8.72 7.8 12.8 1.67 0 0 1.84 20.3 1.56
2.52 1240 7.58 6.7 27.8 2.17 0 0 2.34 20.3 1.44
3.03 920 4.22 3.9 26.3 2.68 0 0 2.85 11.7 1.46
3.53 880 3.92 3.1 -6 3.19 0 0 3.36 11.7 1.46
4.05 1120 10.39 9.4 24.8 3.7 0 0 3.87 11.7 1.48
4.55 1320 14.64 14.1 20.3 4.21 0 0 4.38 19.5 1.56
5.05 1800 18.94 17.3 12.8 4.72 0 0 4.88 20.3 1.58
5.57 2160 13.72 10.2 31.5 5.22 0 0 5.39 17.2 1.52
6.08 2360 7.36 6.3 34.5 5.74 0 0 5.9 1.6 1.18
6.58 2360 5.42 4.7 3 6.25 0 0 6.41 -7 1.28
7.08 2240 5.67 4.7 3 6.74 0 0 6.92 21.9 2.06
7.59 2120 5.53 4.7 2.3 7.25 0 0 7.42 27.3 1.94
8.1 1920 5.11 4.3 1.5 7.76 0 0 7.93 0 3.26
8.61 1720 4.64 3.5 0 8.28 0 0 8.44 0 3.9
9.11 1480 3.83 3.1 -1.5 8.77 0 0 8.94 0 4.02
9.63 1240 3.31 2.4 7.5 9.29 0 0 9.47 0 3.86
10.14 1080 3.11 2.4 6.8 9.8 0 0 9.97 0 3.12
10.64 1040 5.72 5.1 28.5 10.31 0 0 10.47 0 2.74
11.16 1160 9.72 9 24.8 10.82 0 0 10.98 0 2.2
11.66 1320 11.69 11 24.8 11.32 0 0 11.49 0 1.78
12.18 1560 12.64 10.6 27 11.83 0 0 12.01 0 1.74
12.67 1760 17.03 14.9 23.3 12.34 0 0 12.51 0 1.74
13.18 2000 22.08 18 14.3 12.84 0 0 13.01 0 1.74
13.69 2240 26.19 19.6 27 13.35 0 0 13.52 0 1.84
14.2 2480 31.64 22.7 27.8 13.86 0 0 14.03 0 1.94
14.74 2880 39.14 24.3 27 14.37 0 0 14.56 22.7 1.74
15.25 3200 37.03 20.8 27.8 14.91 0 0 15.08 24.2 1.48
15.76 3440 29.69 16.1 33 15.42 0 0 15.59 25 1.6
16.26 3520 17.83 12.2 40.5 15.93 0 0 16.1 11.7 1.1
16.77 3480 18.25 12.2 40.5 16.45 0 0 16.61 1.6 1.52
17.29 3400 17.92 12.2 40.5 16.94 0 0 17.11 5.5 1.58
17.79 3360 16.58 11.8 40.5 17.45 0 0 17.62 15.6 1.54
18.3 3280 13.56 9.8 41.3 17.96 0 0 18.13 16.4 1.56


MAF number seems to be back in normal operating parameters at warm idle. I notice that the STFT is wayyy up at idle as soon as the MAF is plugged in and the car is idling. I'm wondering, since without the MAF it was not that high and by plugging the MAF back in it jumps, if a "dead" MAF is possibly the issue. I did not notice a change in idle with the MAF unplugged vs. plugged in nor did I try to "clean" the MAF while it was unplugged. Was hoping to get some feedback on the logs before trying anything else.

Thanks in advance!
AJ

[old guy]

Pretty much all your logs indicate that when you are getting input from your MAF sensor you are seeing a large amount of fuel add in both the idle trims and the partial trims. Your boost leak test didn't find anything to indicate false air that could contribute to that condition. There is one more thing you can check. What is the maximum g/s flow that your MAF sensor indicates at WOT? If that reads lower than expected I would think it's time to replace the MAF sensor.

[Prospect25]

Pretty much all your logs indicate that when you are getting input from your MAF sensor you are seeing a large amount of fuel add in both the idle trims and the partial trims. Your boost leak test didn't find anything to indicate false air that could contribute to that condition. There is one more thing you can check. What is the maximum g/s flow that your MAF sensor indicates at WOT? If that reads lower than expected I would think it's time to replace the MAF sensor.

Here are two logs in third gear at WOT.


Wednesday 22 June 2016 20:43:01:02193-VCID:336566E5513DF9A6B3-5140 VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '003 Group B: '032 Group C: '033
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (G70) Timing Angle TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP % % STAMP % V
0.1 1880 2.36 3.9 1.5 0.27 0.6 12.5 0.44 11.7 1.66
0.61 1520 22.08 18.8 22.5 0.78 0.6 12.5 0.95 0 1
1.12 1640 21.64 94.1 17.3 1.3 0.6 12.5 1.46 -4.7 1.26
1.62 1720 23.42 99.6 18 1.79 0.6 12.5 1.97 -3.1 1.16
2.14 1880 27.53 100 18 2.31 0.6 12.5 2.48 1.6 1.22
2.66 2000 33.08 100 14.3 2.83 0.6 12.5 3 6.3 1.1
3.17 2160 38.67 100 12.8 3.34 0.6 12.5 3.5 7 0.96
3.66 2320 45.06 100 9.8 3.84 0.6 12.5 4.01 7.8 1
4.18 2480 55.69 100 10.5 4.36 0.6 12.5 4.53 7.8 0.98
4.7 2680 71.69 100 5.3 4.87 0.6 12.5 5.03 7 0.8
5.19 2840 89.67 100 0.8 5.36 0.6 12.5 5.54 0 0.86
5.71 3080 103.61 100 0.8 5.88 0.6 12.5 6.04 1.6 1.06
6.21 3280 116.75 100 -3 6.38 0.6 12.5 6.55 5.5 0.9
6.72 3520 122.5 100 -1.5 6.89 0.6 12.5 7.07 5.5 0.86
7.24 3720 124.11 100 0 7.41 0.6 12.5 7.59 1.6 0.9
7.76 3920 125.89 100 1.5 7.92 0.6 12.5 8.08 0 0.84
8.25 4080 129.17 100 3.8 8.42 0.6 12.5 8.59 -1.6 0.88
8.76 4240 131.67 100 4.5 8.93 0.6 12.5 9.1 -2.3 0.82
9.27 4400 132.44 100 5.3 9.44 0.6 12.5 9.61 -3.1 0.82
9.78 4560 132.92 100 6 9.95 0.6 12.5 10.12 -4.7 0.84
10.29 4680 133.44 100 6 10.46 0.6 12.5 10.63 -3.9 0.78
10.81 4800 136 100 6 10.97 0.6 12.5 11.14 -3.1 0.56
11.31 4880 135.11 100 5.3 11.48 0.6 12.5 11.65 -3.1 0.52
11.82 5000 135.11 100 3.8 11.99 0.6 12.5 12.17 -2.3 0.42
12.34 5080 135.5 100 3 12.51 0.6 12.5 12.67 -1.6 0.3
12.84 5160 137.78 100 6 13.01 0.6 12.5 13.18 -1.6 0.22
13.35 5200 45.5 13.3 0 13.53 0.6 12.5 13.69 0 0.7



Wednesday 22 June 2016 20:46:38:02193-VCID:336566E5513DF9A6B3-5140 VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '003 Group B: '032 Group C: '033
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (G70) Timing Angle TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP % % STAMP % V
0 2280 40.47 100 18 0.17 0.4 15.6 0.34 4.7 1.3
0.52 2440 48.06 100 15.8 0.7 0.4 15.6 0.87 3.9 1.14
1.05 2560 57.64 100 10.5 1.22 0.4 15.6 1.39 4.7 1.22
1.56 2720 71.94 100 4.5 1.73 0.4 15.6 1.9 3.9 1
2.07 2880 92.08 100 -0.8 2.24 0.4 15.6 2.41 -1.6 1.12
2.58 3080 103.33 100 0 2.75 0.4 15.6 2.92 -0.8 1.12
3.09 3280 112.97 100 -3 3.26 0.4 15.6 3.43 1.6 1.04
3.61 3480 119.08 100 -2.3 3.78 0.4 15.6 3.94 2.3 1.04
4.11 3680 121.14 100 -0.8 4.28 0.4 15.6 4.45 -1.6 0.96
4.62 3880 125.42 100 0.8 4.79 0.4 15.6 4.96 -1.6 0.94
5.14 4040 127.47 100 1.5 5.3 0.4 15.6 5.47 -3.1 0.9
5.64 4240 128.69 100 6 5.81 0.4 15.6 5.98 -3.9 0.96
6.17 4440 131.81 100 6 6.33 0.4 15.6 6.51 -7 0.86
6.68 4600 131.64 100 6.8 6.85 0.4 15.6 7.02 -6.3 0.78
7.19 4760 133.06 99.6 6 7.36 0.4 15.6 7.53 -5.5 0.62
7.7 4920 135.11 100 3.8 7.87 0.4 15.6 8.05 -5.5 0.5
8.22 5080 134.53 100 6 8.4 0.4 15.6 8.57 -4.7 0.38
8.73 5200 134.36 100 8.3 8.9 0.4 15.6 9.06 -3.9 0.3
9.23 5360 136.08 100 9.8 9.4 0.4 15.6 9.57 -3.1 0.36
9.75 5480 135.06 100 9.8 9.92 0.4 15.6 10.1 -4.7 0.38
10.27 5600 137.33 100 14.3 10.43 0.4 15.6 10.59 -3.9 0.48
10.76 5720 135.5 99.6 12 10.93 0.4 15.6 11.1 -3.1 0.4
11.27 5840 135.97 99.6 12 11.44 0.4 15.6 11.63 -2.3 0.36



It looks like the MAF g/s reading never went above 137.78 from the first log. I've read that the g/s reading should be around 80% of the HP at the flywheel, but maybe that's an old wives tale. If that's true, should my readings be up closer to 180-190 on an APR tune with larger TT225 injectors? If so, this may point to a faulty MAF.

Although, i have another point. The 1.8T makes 179 HP stock, so 80% of that number would be about 140 g/s which is pretty close to the highest value read. I knew a guy who had a B5 S4 with an APR tune and he was having similar boost issues. He had his ECU reflashed and that solved his problem. Is it plausible that the fuel trims are so high because of the TT225 injectors with a possible "stock" tune, therefore causing it to run rich?

Just a thought.... Looking forward to hearing yours.

AJ

[old guy]

Stock 1.8T is 170 hp and the typical MAF reading is around 135 g/s. If you are running a APR big injector file you should be seeing something around 160→170 g/s.

Based upon some of your previous logs you are definately not running on a stock tune. Stock boost maximum is around 11 psi. And you are not running rich. The high amount of fuel add is to make up for the high amount of unmetered air entering your engine. So it's either getting sucked in after the MAF sensor or the sensor itself isn't reading properly. You didn't find anything with a boost pressure test so the next most logical explanation is the MAF sensor isn't reading properly.

Clean your MAF and see if it makes a difference. If not, consider replacing the MAF sensor.

Good luck!

[Prospect25]

Stock 1.8T is 170 hp and the typical MAF reading is around 135 g/s. If you are running a APR big injector file you should be seeing something around 160→170 g/s.

Based upon some of your previous logs you are definately not running on a stock tune. Stock boost maximum is around 11 psi. And you are not running rich. The high amount of fuel add is to make up for the high amount of unmetered air entering your engine. So it's either getting sucked in after the MAF sensor or the sensor itself isn't reading properly. You didn't find anything with a boost pressure test so the next most logical explanation is the MAF sensor isn't reading properly.

Clean your MAF and see if it makes a difference. If not, consider replacing the MAF sensor.

Good luck!

Thanks old guy. You were up late (or really early) and i appreciate your feedback. I have electronics cleaner but am going to try to track down some 99% alcohol to clean off the sensor. I'd rather give cleaning it a try before spending $100 on a new one. If it gives the same readings i'll go back and do another boost test to triple check there is no unmetered air and then go from there.

I'll keep you posted with my results!

AJ

[Prospect25]

Thanks old guy. You were up late (or really early) and i appreciate your feedback. I have electronics cleaner but am going to try to track down some 99% alcohol to clean off the sensor. I'd rather give cleaning it a try before spending $100 on a new one. If it gives the same readings i'll go back and do another boost test to triple check there is no unmetered air and then go from there.

I'll keep you posted with my results!

AJ

Pulled the MAF with a 5 point tamper proof Torx, size T25, and cleaned it all over with MAF cleaner. Sprayed it down a few times to be sure i got every nook and cranny. Reinstalled and left in car overnight. Did a log the next day and here are the results:

Saturday 25 June 2016 17:03:48:02193-VCID:336566E5513DF9A6B3-515E VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '003 Group B: '032 Group C: '033
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (G70) Timing Angle TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP % % STAMP % V
0.41 1960 26.89 99.6 18 0.09 0.4 0 0.25 7 1.64
0.93 2040 30.89 99.6 18 0.58 0.4 0 0.76 15.6 1.28
1.44 2120 34.67 100 14.3 1.1 0.4 0 1.27 20.3 1.16
1.96 2240 39.64 100 11.3 1.62 0.4 0 1.79 21.9 1.06
2.48 2360 43.89 100 12.8 2.13 0.4 0 2.3 22.7 1.06
2.99 2480 51.14 100 12.8 2.65 0.4 0 2.82 22.7 0.94
3.5 2560 56.72 100 8.3 3.17 0.4 0 3.33 21.9 1.02
4.01 2680 66.83 100 8.3 3.67 0.4 0 3.84 22.7 1.02
4.52 2840 76.42 100 1.5 4.18 0.4 0 4.35 22.7 0.98
5.03 2960 91.19 100 1.5 4.7 0.4 0 4.87 18.8 0.76
5.53 3120 100.56 100 -1.5 5.2 0.4 0 5.37 14.8 0.92
6.05 3280 106.75 99.6 -0.8 5.7 0.4 0 5.87 14.8 0.96
6.56 3440 110.19 100 0 6.22 0.4 0 6.4 14.8 0.92
7.08 3560 116.31 100 -0.8 6.73 0.4 0 6.91 15.6 0.92
7.59 3720 118.75 100 0.8 7.25 0.4 0 7.42 16.4 0.9
8.12 3880 122.28 100 2.3 7.78 0.4 0 7.95 14.1 0.84
8.61 4000 122.69 100 3.8 8.28 0.4 0 8.44 14.1 0.9
9.13 4160 122.97 100 5.3 8.78 0.4 0 8.95 14.1 0.88
9.65 4320 125.78 100 6 9.29 0.4 0 9.47 11.7 0.8
10.12 4440 129 100 6 9.8 0.4 0 9.96 10.9 0.84
10.63 4560 129.17 100 6 10.29 0.4 0 10.46 8.6 0.82
11.15 4680 129.44 100 6 10.8 0.4 0 10.98 7.8 0.62
11.65 4800 131.22 100 6 11.31 0.4 0 11.48 7.8 0.58
12.16 4920 131.5 100 5.3 11.82 0.4 0 11.99 8.6 0.54
12.67 5040 131.58 100 7.5 12.33 0.4 0 12.5 7.8 0.46
13.18 5120 131.22 100 6 12.84 0.4 0 13.01 7 0.48
13.69 5200 133.06 100 8.3 13.35 0.4 0 13.52 7 0.48
14.21 5320 132.86 100 9.8 13.86 0.4 0 14.04 6.3 0.48
14.68 5400 131.89 100 8.3 14.37 0.4 0 14.52 7 0.5
15.2 5480 133.22 100 11.3 14.86 0.4 0 15.03 7.8 0.46
15.71 5560 133.22 100 9.8 15.37 0.4 0 15.55 7.8 0.48
16.2 5640 134.53 100 9.8 15.87 0.4 0 16.04 7 0.44
16.72 5720 134.83 100 9 16.37 0.4 0 16.55 7.8 0.46


MAF g/s reading still wouldn't go over ~135 so I think we all can conclude the MAF is dead. Ordered a new one from ECS for $100, plus a J219 Relay since my fans would turn on and off intermittently plus a new door harness since driver window won't open and door won't lock plus some clips and stuff for an oil change :( Hopefully these are the last maintenance items for a long time!! Once I get the new MAF installed i'll be sure to log again and let you know if the problem is fixed.

Thank you again for your guidance, and I hope this thread is helpful to someone else in the future

[Prospect25]

Back for an update! Ordered my parts from ECS and they took a week to ship them out because of a stocking order on their end. Then i was out of town for two weeks so i just finally had an opportunity to install the new MAF.

Upon installation, i logged the 003 block and here are the results:

Group A: '003 Group B: '032 Group C: '033
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (G70) Timing Angle TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP % % STAMP % V
0.34 1520 19.64 82.7 16.5 0 0.8 14.8 0.17 -3.1 1.04
0.83 1600 20.94 88.6 9 0.5 0.8 14.8 0.66 -3.9 1.06
1.36 1680 23.47 96.1 15.8 1.02 0.8 14.8 1.2 -4.7 0.96
1.85 1800 25.08 100 14.3 1.52 0.8 14.8 1.68 -6.3 0.94
2.36 1880 28.44 100 11.3 2.02 0.8 14.8 2.19 -5.5 1.02
2.88 2000 31.47 100 14.3 2.53 0.8 14.8 2.71 -0.8 1.08
3.38 2080 34.92 100 9.8 3.05 0.8 14.8 3.21 2.3 1
3.89 2200 39.11 100 9 3.55 0.8 14.8 3.72 3.9 1
4.41 2280 44.75 100 9 4.06 0.8 14.8 4.23 4.7 0.94
4.93 2440 49.56 100 9 4.59 0.8 14.8 4.76 4.7 0.9
5.44 2520 57.78 100 8.3 5.1 0.8 14.8 5.27 3.9 0.98
5.91 2640 66.36 100 3.8 5.6 0.8 14.8 5.76 6.3 0.94
6.41 2760 77.33 100 -0.8 6.07 0.8 14.8 6.23 5.5 0.88
6.92 2920 93.03 100 -1.5 6.58 0.8 14.8 6.75 0.8 0.66
7.43 3040 98.97 100 -2.3 7.09 0.8 14.8 7.26 -2.3 0.94
7.95 3200 107.44 100 -3 7.61 0.8 14.8 7.78 -2.3 0.92
8.45 3360 109.33 100 -2.3 8.11 0.8 14.8 8.28 -0.8 0.9
8.96 3520 115.31 100 -2.3 8.6 0.8 14.8 8.78 -0.8 0.9
9.48 3640 119.89 100 -1.5 9.13 0.8 14.8 9.31 0.8 0.88
9.98 3800 120.64 100 0 9.65 0.8 14.8 9.81 0 0.84
10.48 3960 123.17 100 0.8 10.15 0.8 14.8 10.31 -1.6 0.86
10.99 4080 124 100 2.3 10.65 0.8 14.8 10.82 -1.6 0.86
11.5 4240 126.39 100 3.8 11.16 0.8 14.8 11.33 -2.3 0.84
12 4360 127.14 100 6 11.69 0.8 14.8 11.85 -3.9 0.82
12.52 4520 129.61 100 4.5 12.18 0.8 14.8 12.35 -5.5 0.78
13.03 4640 130.25 100 6.8 12.69 0.8 14.8 12.86 -6.3 0.64
13.53 4760 131.92 100 6 13.2 0.8 14.8 13.37 -6.3 0.62
14.02 4880 131.22 100 5.3 13.69 0.8 14.8 13.85 -6.3 0.46
14.53 4960 131.92 100 5.3 14.19 0.8 14.8 14.36 -5.5 0.44
15.05 5080 132.5 100 6 14.7 0.8 14.8 14.87 -4.7 0.3
15.53 5160 133.64 100 5.3 15.22 0.8 14.8 15.37 -3.9 0.18
16.04 5280 131.75 100 7.5 15.7 0.8 14.8 15.87 -3.1 0.12
16.56 5360 131.94 99.6 10.5 16.22 0.8 14.8 16.39 -2.3 0.08
17.07 5440 133.47 100 10.5 16.73 0.8 14.8 16.91 -1.6 0.12
17.57 5520 132.11 100 12.8 17.23 0.8 14.8 17.4 -1.6 0.14
18.09 5640 134.36 100 12 17.74 0.8 14.8 17.92 -1.6 0.18
18.6 5720 133.03 100 12.8 18.26 0.8 14.8 18.43 -0.8 0.16
19.11 5800 135.06 100 15 18.76 0.8 14.8 18.93 -0.8 0.18


The g/s reading still would not go above 135 and it is a brand new MAF. I'm starting to think this issue is being caused by something else. I was driving the other day and still experienced low boost in 5th gear at a cruising speed around 65-70mph. When i would go to punch it, boost would not rise above 5-6PSI. I finally got a check engine light today after about 200 miles of driving and i did a pull in third gear which shows the MAF reading, requested vs. actual boost, and long term fuel trim:

Group A: '003 Group B: '115 Group C: '032
Engine Speed Mass Air Flow Throttle Valve Angle Ignition Engine Speed Engine Load Boost Pressure Boost Pressure Adaptation (Idle) Adaptation (Partial)
TIME (G28) (G70) Timing Angle TIME (G28) (specified) (actual) TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min g/s % °BTDC STAMP /min % mbar mbar STAMP % %
0.11 2600 14.47 11 38.3 0.28 2600 28.6 820 990 0.45 -0.4 22.7
0.64 2320 0 5.1 6.8 0.8 2200 15.8 820 930 0.96 -0.4 22.7
1.13 2080 39.56 43.1 22.5 1.3 1480 62.4 1470 890 1.46 -0.4 22.7
1.63 1720 21.83 94.5 7.5 1.79 1680 63.9 1530 950 1.95 -0.4 22.7
2.12 1680 22.61 95.7 14.3 2.29 1720 66.9 1530 980 2.47 -0.4 22.7
2.64 1760 23.42 98.8 8.3 2.81 1760 69.2 1540 1010 2.98 -0.4 22.7
3.15 1800 24.28 100 16.5 3.33 1800 70.7 1560 1040 3.5 -0.4 22.7
3.66 1840 25.81 100 12.8 3.82 1840 72.9 1580 1050 4 -0.4 22.7
4.17 1880 27.31 100 13.5 4.35 1920 74.4 1610 1070 4.52 -0.4 22.7
4.69 1960 28.44 100 12.8 4.87 2000 75.2 1630 1070 5.03 -0.4 22.7
5.2 2040 29.39 99.6 15.8 5.37 2040 75.9 1660 1070 5.54 -0.4 22.7
5.71 2080 30.97 100 16.5 5.88 2120 75.9 1680 1070 6.06 -0.4 22.7
6.24 2160 32.61 100 16.5 6.41 2200 76.7 1710 1090 6.58 -0.4 22.7
6.75 2200 33.11 100 13.5 6.92 2240 77.4 1760 1090 7.09 -0.4 22.7
7.26 2280 35.31 100 14.3 7.43 2320 78.9 1840 1110 7.62 -0.4 22.7
7.8 2360 36.92 100 17.3 7.98 2400 81.2 1940 1130 8.14 -0.4 22.7
8.3 2440 38.72 100 18.8 8.46 2480 82.7 2000 1150 8.63 -0.4 22.7
8.8 2520 42.42 100 16.5 8.98 2560 85 2050 1160 9.14 -0.4 22.7
9.32 2600 43.14 100 16.5 9.49 2640 85.7 2090 1160 9.67 -0.4 22.7
9.84 2680 45.06 100 15 10.01 2720 87.2 2110 1180 10.18 -0.4 22.7
10.35 2760 46.56 100 16.5 10.52 2800 88.7 2150 1190 10.7 -0.4 22.7
10.87 2840 49 100 15 11.03 2880 90.2 2190 1200 11.19 -0.4 22.7
11.37 2920 51.22 100 15 11.54 2960 91 2230 1210 11.7 -0.4 22.7
11.87 3040 52.81 100 15.8 12.03 3040 91 2240 1210 12.2 -0.4 22.7
12.38 3120 53.67 99.6 13.5 12.55 3120 92.5 2250 1220 12.72 -0.4 22.7
12.89 3200 58.33 100 14.3 13.07 3240 94 2250 1230 13.24 -0.4 22.7
13.41 3280 59.53 100 13.5 13.58 3320 95.5 2260 1230 13.74 -0.4 22.7
13.91 3400 62.56 100 14.3 14.09 3400 96.2 2270 1230 14.25 -0.4 22.7
14.42 3480 64 100 13.5 14.59 3520 97 2280 1230 14.77 -0.4 22.7
14.95 3560 67.25 100 13.5 15.12 3600 97 2280 1260 15.29 -0.4 22.7
15.46 3680 68.14 100 13.5 15.63 3680 95.5 2280 1240 15.8 -0.4 22.7
15.97 3760 69.94 100 15 16.14 3800 97 2280 1260 16.31 -0.4 22.7
16.49 3840 72.56 100 13.5 16.67 3880 97 2260 1250 16.84 -0.4 22.7
17 3960 73.47 100 14.3 17.18 4000 96.2 2260 1250 17.34 -0.4 22.7
17.51 4040 74.97 100 15.8 17.67 4080 97 2230 1250 17.84 -0.4 22.7
18.01 4160 77 100 15 18.19 4160 97.7 2200 1250 18.35 -0.4 22.7
18.52 4240 79.17 100 15 18.69 4280 97.7 2170 1260 18.86 -0.4 22.7
19.03 4320 81.42 100 15 19.2 4360 98.5 2150 1270 19.36 -0.4 22.7
19.53 4440 83.44 100 15.8 19.7 4480 98.5 2120 1270 19.87 -0.4 22.7
20.05 4520 86.97 100 15.8 20.22 4560 100 2090 1270 20.39 -0.4 22.7
20.56 4640 88.39 100 15.8 20.73 4680 100.8 2060 1270 20.9 -0.4 22.7
21.07 4720 93.25 99.6 14.3 21.23 4760 101.5 2030 1270 21.4 -0.4 22.7
21.57 4840 95.06 100 15 21.75 4880 101.5 2000 1270 21.91 -0.4 22.7
22.08 4920 96.86 100 14.3 22.25 4960 103 1970 1270 22.43 -0.4 22.7
22.6 5040 100.31 100 14.3 22.76 5080 103 1940 1290 22.93 -0.4 22.7
23.1 5120 101.81 100 15 23.26 5160 103.8 1910 1290 23.43 -0.4 22.7
23.61 5240 104 100 16.5 23.78 5240 104.5 1870 1280 23.95 -0.4 22.7
24.13 5320 104.92 100 18 24.29 5360 100.8 1820 1260 24.45 -0.4 22.7
24.61 5400 103 100 18.8 24.78 5440 98.5 1790 1210 24.96 -0.4 22.7
25.13 5480 103.53 100 20.3 25.29 5520 98.5 1760 1200 25.47 -0.4 22.7
25.63 5560 102.64 100 17.3 25.8 5680 96.2 810 1180 25.97 -0.4 22.7
26.14 5760 0 8.6 14.3 26.31 5560 14.3 810 1100 26.48 -0.4 22.7
26.65 5240 13.22 9.4 11.3 26.82 4360 15 810 990 26.98 -0.4 22.7


I'm starting to think it has to do with the motor not getting enough fuel at higher speeds. The place I ordered the fuel pump and fuel filters from is sending me replacements under warranty. Any other ideas on what the heck it could be?

AJ

[CyberPMG]

Since you've replaced the fuel pump, fuel filter, and MAF, it might be a good idea to check the fuel injector seats (what the injectors fit into). They're plastic and will become brittle and crack over time. They're supposed to be white. If they are looking yellow, that's a good indication of fuel leaking out and discoloring them. If those are OK, you may want to check the ignition coil wire harness for signal strength. Could be a cracked wire that you can't see which could cut out signal and cause misfires. The wires undergo a lot of heat stress from the heat cycles of the engine.

[Prospect25]

Since you've replaced the fuel pump, fuel filter, and MAF, it might be a good idea to check the fuel injector seats (what the injectors fit into). They're plastic and will become brittle and crack over time. They're supposed to be white. If they are looking yellow, that's a good indication of fuel leaking out and discoloring them. If those are OK, you may want to check the ignition coil wire harness for signal strength. Could be a cracked wire that you can't see which could cut out signal and cause misfires. The wires undergo a lot of heat stress from the heat cycles of the engine.

I haven't thought of the injector seats yet; thanks for the suggestion! I'm going to be replacing the pump and filter this week.

Would a potential loss of strength in the ignition coil cause a long term lean code? I suppose I don't understand the correlation.

More to come!

AJ

[tnapp]

My car had a similar random misfire issue, ended up being the fuel filter. It was just about completely clogged. Replacing the filter made a night and day difference.

[old guy]

Looking at your logs it appears that you are not coming anywhere near your requested boost. Also, did you run the group 32/33 before the group 115/32? If I am reading them correctly your LTFT in the first log went to 14.8% and by the second log went to 22.7%. That's some serious fuel add.

After all you have done and replaced it's probably worth checking your fuel pressure at the fuel rail. ECS tuning has an inexpensive gauge that you can insert into the fuel line for a quick check.

[Prospect25]

My car had a similar random misfire issue, ended up being the fuel filter. It was just about completely clogged. Replacing the filter made a night and day difference.

Looking at your logs it appears that you are not coming anywhere near your requested boost. Also, did you run the group 32/33 before the group 115/32? If I am reading them correctly your LTFT in the first log went to 14.8% and by the second log went to 22.7%. That's some serious fuel add.

After all you have done and replaced it's probably worth checking your fuel pressure at the fuel rail. ECS tuning has an inexpensive gauge that you can insert into the fuel line for a quick check.

In one of the logs, my car did have a CEL and was in boost mode which would explain the discrepancy in actual vs requested boost. I'm still wondering why my g/s is still hovering at the same level...

I just replaced the fuel filter, fuel pump, SAI pump, fuel injector seals this weekend with a few other maintenance items and have been driving the car normally all week. The CEL has yet to come back on (fingers crossed) and i will do some logs this week to determine if the issue has been taken care of. Will keep everyone posted; thank you much for your help and guidance!

AJ

[Prospect25]

Should have knocked on wood; CEL illuminated on my drive home from work yesterday. Hooked it up to VAGCOM and revealed the following codes:

P1114 - 008 - Internal Resistance too High - Intermittent
P1136 - 001 - System too Lean - MIL ON

Also logged 032, 033, and 003 when i parked at my house and my fuel trim was hella high:

Wednesday 10 August 2016 19:57:14:02193-VCID:336566E5513DF9A6B3-5140 VCDS Version: Release 15.7.4 (x64) Data version: 20160216
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '032 Group B: '033 Group C: '003
Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage Engine Speed Mass Air Flow Throttle Valve Angle Ignition
TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME (G28) (G70) Timing Angle
Marker STAMP % % STAMP % V STAMP /min g/s % °BTDC
0.17 3.6 0 0.34 27.3 1.96 0 760 1.92 1.2 3
0.68 3.8 0 0.86 27.3 1.98 0.51 760 1.92 1.2 3
1.2 3.8 0 1.37 21.9 1.96 1.03 760 1.92 1.2 2.3
1.71 3.8 0 1.88 21.9 1.96 1.54 760 1.92 1.2 3
2.23 3.9 0 2.4 21.9 1.96 2.05 760 1.92 1.2 6
2.75 3.9 0 2.92 21.9 1.92 2.57 760 1.94 1.2 3
3.26 3.9 0 3.43 27.3 1.92 3.09 800 1.94 1.2 2.3
3.78 4.1 0 3.94 27.3 1.9 3.6 800 1.94 1.2 0

I realize it was only a short log but hitting a change of 27% seems borderline catastrophic. Back to one of my original thoughts, could this be a tuning problem or am i just going to have to replace every little thing in this car before it runs normal? I'm starting to feel like i'm just throwing good money at bad money with no end in sight. Help!

[Prospect25]

New codes today after clearing yesterday:

P1136 - 001 - System too Lean - MIL ON
P0507 - 001 - Higher than Expected - Intermittent
P0300 - 001 - Random/Multiple Cylinder Misfire Detected
P0304 - 001 - Cylinder 4 Misfire Detected

I have a set of new coils, should i just swap them out and throw some new plugs in and see how it goes? This is all driving me mad!

[old guy]

The P1136 and P0507 both indicate an an air leak at idle. That is also probably what is causing the P03XX misfire codes. You need to find the source of false air at idle.

[Prospect25]

The P1136 and P0507 both indicate an an air leak at idle. That is also probably what is causing the P03XX misfire codes. You need to find the source of false air at idle.

Looks like i will be hooking it up to my home made air leak tester this weekend. Hopefully it's an easy fix, if there is such a thing

[Prospect25]

UPDATE: Found the source of false air at idle - the injector seats must have cracked when new o-rings were installed on the injectors. I could hear the noise coming from the intake manifold area but could not pinpoint exactly where. I started clamping off lines and was beside myself when nothing happened. I pulled the injectors and saw huge cracks in the seats. Replaced all 4 at $5 a pop and now it's idling great.

Ultimately, i can't say i was able to exactly pinpoint the issue but i believe it had something to do with issues with the fuel filter or fuel pump. I still haven't had time to get out and give it a few proper pulls and log them, but that is something to put on my honey-do list for Labor Day weekend. Thanks everyone for the guidance and advice!

[Prospect25]

Hey all! Car has been running well for the past few weeks *knock on wood* No CELs and feels great under full boost. Did a much overdue log tonight. My the multiplicative value seems a little higher than the +- 10%. Any thoughts?

Tuesday 20 September 2016 18:42:51:02193-VCID:336566E5513DF9DA6D-5140 VCDS Version: Release 16.8.0 (x64) Data version: 20160803 DS255
8E0 909 518 F 1.8L R4/5VT G 0004

Group A: '115 Group B: '032 Group C: '033
Engine Speed Engine Load Boost Pressure Boost Pressure Adaptation (Idle) Adaptation (Partial) Lambda Control Sensor Voltage
TIME (G28) (specified) (actual) TIME Bank 1 Sensor 1 Bank 1 Sensor 1 TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP /min % mbar mbar STAMP % % STAMP % V
0.17 2000 45.9 810 920 0.34 0.9 16.4 0 -7.8 1.5
0.68 2080 42.9 810 930 0.84 0.9 16.4 0.51 -6.3 1.5
1.19 2160 42.9 810 930 1.36 0.9 16.4 1.02 0.8 1.48
1.7 2280 48.1 1050 930 1.87 0.9 16.4 1.53 2.3 1.6
2.21 2320 28.6 810 980 2.38 0.9 16.4 2.04 8.6 1.64
2.71 2160 28.6 1750 900 2.89 0.9 16.4 2.54 0 0.84
3.23 1720 63.9 1590 940 3.4 0.9 16.4 3.06 0 0.88
3.74 1760 67.7 1550 1000 3.92 0.9 16.4 3.57 -5.5 1.06
4.25 1840 70.7 1560 1040 4.41 0.9 16.4 4.09 -8.6 1.04
4.76 1920 74.4 1580 1090 4.93 0.9 16.4 4.59 -7 1.1
5.27 2000 78.9 1620 1130 5.45 0.9 16.4 5.1 -3.1 1.12
5.79 2080 83.5 1640 1190 5.96 0.9 16.4 5.62 -0.8 1.04
6.3 2200 88.7 1650 1260 6.48 0.9 16.4 6.13 0 1.02
6.82 2320 97.7 1730 1360 6.99 0.9 16.4 6.65 1.6 0.98
7.33 2440 106.8 1850 1470 7.5 0.9 16.4 7.16 0 0.9
7.84 2560 118 1940 1620 8.01 0.9 16.4 7.67 0 0.98
8.35 2680 133.8 2050 1810 8.52 0.9 16.4 8.19 1.6 0.96
8.86 2840 157.9 2140 2090 9.03 0.9 16.4 8.69 -1.6 0.78
9.37 3000 173.7 2230 2280 9.54 0.9 16.4 9.2 -6.3 0.92
9.88 3160 179.7 2230 2340 10.05 0.9 16.4 9.7 -4.7 0.9
10.39 3320 181.2 2240 2310 10.56 0.9 16.4 10.22 -3.9 0.92
10.9 3480 178.9 2250 2250 11.07 0.9 16.4 10.73 -3.1 0.92
11.41 3640 173.7 2240 2250 11.57 0.9 16.4 11.24 -3.1 0.88
11.92 3800 169.9 2220 2210 12.09 0.9 16.4 11.74 -5.5 0.88
12.43 3960 164.7 2220 2160 12.6 0.9 16.4 12.26 -5.5 0.9
12.95 4120 160.2 2170 2130 13.12 0.9 16.4 12.78 -5.5 0.88
13.47 4280 155.6 2140 2070 13.64 0.9 16.4 13.29 -6.3 0.84
13.98 4440 151.9 2100 2010 14.15 0.9 16.4 13.81 -9.4 0.8
14.49 4560 148.9 2050 1960 14.66 0.9 16.4 14.32 -10.9 0.56
15.01 4720 145.9 2010 1890 15.17 0.9 16.4 14.83 -10.9 0.5
15.53 4840 142.1 1960 1840 15.69 0.9 16.4 15.35 -8.6 0.38
16.02 4960 139.1 1940 1800 16.19 0.9 16.4 15.85 -7 0.24
16.53 5080 136.1 1890 1750 16.7 0.9 16.4 16.36 -5.5 0.14
17.05 5200 133.8 1850 1710 17.21 0.9 16.4 16.88 -4.7 0.08
17.55 5320 129.3 1810 1680 17.72 0.9 16.4 17.38 -3.9 0.02
18.06 5440 127.1 1760 1650 18.23 0.9 16.4 17.89 -3.1 0.02
18.58 5560 124.8 1730 1620 18.75 0.9 16.4 18.4 -8.6 0.36
19.08 5680 123.3 1700 1600 19.25 0.9 16.4 18.91 -8.6 0.48
19.59 5760 121.1 1670 1610 19.76 0.9 16.4 19.42 -7 0.36
20.1 5840 112.8 810 1690 20.26 0.9 16.4 19.93 -5.5 0.22
20.61 5440 14.3 810 1200 20.78 0.9 16.4 20.44 0.8 1.3
21.12 5080 13.5 810 960 21.29 0.9 16.4 20.95 -2.3 1.1
21.63 4400 13.5 810 940 21.82 0.9 16.4 21.46 -4.7 1.34


AJ