Hi all,
I bought a 2013 A4 Quattro B8.5 with a CPMA 2.0 Turbo engine three weeks ago. I took the car to a mechanic to do a pre purchase inspection and the mechanic scanned it, and there were no engine codes stored.
A week after, the car started throwing EPC lights. I then bought an OBDEleven with Pro subscription and scanned the car. Initially it started giving P304300 - Fuel pump mechanical malfunction codes together with P310B00 - Low Fuel Pressure regulation Fuel pressure outside specification. The EPC light would turn off, every time I switched the engine off, and it would take a while to come back on again. After a while it started coming on way more frequently, and would often turn on every time a few minutes after I started the engine.
I looked up online and these codes could be caused either by a failure in the low pressure (in-tank) fuel pump itself, its control module, or there could be dirty/clogged/faulty fuel lines. I didn't want to replace the fuel pump without being sure this was the problem, so I grabbed a fuel pressure tester kit in AutoZone, but didn't have the time to run the test yet.
Yesterday, I was on a 30+ mile drive and the car started vibrating madly after trying to accelerate to overtake a semi-truck, and it wouldn't stop vibrating anymore until I switched off the engine and then back on. I scanned the car and I got P035400 - Ignition Coil D Primary/secondary Circuit and P230900 - Ignition Coil "D" Primary Control Circuit Low codes besides the usual fuel pump mechanical malfunction codes. Then today, I got this behavior again, and it came together with P030400 - Cyl.4 Misfire Detected and P030000 - Random/Multiple Cylinder Misfire Detected codes.
So I have a few questions:
Are the P035400 - Ignition Coil D Primary/secondary Circuit and P230900 - Ignition Coil "D" Primary Control Circuit Low codes enough to diagnose bad ignition coils, or the problem could be somewhere else, like the coils wiring, for example? I thought I'd replace all coils and spark plugs together, to avoid additional headaches in the near future, but I want to avoid doing that just to find out that the problem is elsewhere.
Can the misfire and the ignition coil problems be caused by a delayed response to the fuel pump problem? I don't see a connection between these malfunctions, but I thought I'd ask anyway.
According to Audi OEM Parts website Apparently there are two options of in-tank fuel pump that I can use, one being significantly cheaper than the other (about half the price). There is the 8K0919051AS (about $460.00) and the 8K0919051AN (about $860.00). I looked it up, and couldn't find much info, but I saw a forum where someone mentioned that the more expensive version is for the fuel flex engine (which is my case), due to the higher flow rate demanded by running on Ethanol. However, I never used ethanol since I got the car, and I have no intention to do so in the foreseeable future. In that case, would I be fine installing the 8K0919051AS, or do I need to get 8K0919051AN for my car (if so, why?)?
Thank you for your help! For those of you who are more interested, these is what the scan from OBDeleven looks like:
OBDeleven data log
Date: 2024-03-15 16:41
Car: Audi A4
Year: 2013
Body type: Saloon
Engine: CPMA
Mileage: 134720 KM
---------------------------------------------------------------
01 Engine
System description: 2.0l R4/4V TF
Trouble codes:
P035400 - Ignition Coil D Primary/secondary Circuit
Intermittent
Date: 2024-03-14 08:27:24
Mileage: 134480 km
Priority: 2
Malfunction frequency counter: 4
Unlearning counter: 255
Engine speed: 5205.50 1/min
Normed load value: 78.0 %
Vehicle speed: 73 km/h
Coolant temperature: 96 °C
Intake air temperature: 21 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 13.075 V
Dynamic environmental data: 209628128C00000F9F133806121615321010097F
P230900 - Ignition Coil "D" Primary Control Circuit Low
Intermittent
Date: 2024-03-14 08:34:53
Mileage: 134495 km
Priority: 2
Malfunction frequency counter: 4
Unlearning counter: 255
Engine speed: 3981.00 1/min
Normed load value: 63.9 %
Vehicle speed: 79 km/h
Coolant temperature: 96 °C
Intake air temperature: 21 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 13.193 V
Dynamic environmental data: 209628128C00000D261338061216131310100831
P304300 - Fuel pump mechanical malfunction
Intermittent
Date: 2024-03-14 08:10:01
Mileage: 134453 km
Priority: 2
Malfunction frequency counter: 5
Unlearning counter: 255
Engine speed: 1530.50 1/min
Normed load value: 5.9 %
Vehicle speed: 39 km/h
Coolant temperature: 95 °C
Intake air temperature: 40 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 14.465 V
Dynamic environmental data: 20962811A445F411CE1959128A9E11C9FD6011D71F8C
P310B00 - Low Fuel Pressure regulation Fuel pressure outside specification
Intermittent
Date: 2024-03-14 09:57:04
Mileage: 134569 km
Priority: 2
Malfunction frequency counter: 1
Unlearning counter: 255
Engine speed: 838.50 1/min
Normed load value: 22.4 %
Vehicle speed: 0 km/h
Coolant temperature: 96 °C
Intake air temperature: 35 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 14.182 V
Dynamic environmental data: 209625128C000006EE133805121604CC1010021A
P030000 - Random/Multiple Cylinder Misfire Detected
Intermittent
Date: 2024-03-15 10:42:04
Mileage: 134698 km
Priority: 2
Malfunction frequency counter: 1
Unlearning counter: 255
Engine speed: 5256.50 1/min
Normed load value: 82.4 %
Vehicle speed: 70 km/h
Coolant temperature: 96 °C
Intake air temperature: 21 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 12.957 V
Dynamic environmental data: 20964D128C00000EF0133806121613F210100BC3
P030400 - Cyl.4 Misfire Detected
Intermittent
Date: 2024-03-15 10:42:22
Mileage: 134698 km
Priority: 2
Malfunction frequency counter: 1
Unlearning counter: 255
Engine speed: 5256.50 1/min
Normed load value: 82.4 %
Vehicle speed: 70 km/h
Coolant temperature: 96 °C
Intake air temperature: 21 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 12.957 V
Dynamic environmental data: 20964D128C00000781133806121608AB101003A8
Reply With Quote
Bookmarks