A4 B8 MAF Sensor P0100 Code.

[Capone28]

Recently I installed a CTS Turbo testpipe with my AWE downpipe and AWE quad touring exhaust. I mounted the o2 sensor spacer on the 2nd part of the testpipe. I then also had to replace my MAF sensor also, so I plugged the new one in and started the car with my IE Stage 2. The CEL, TPMS, Park brake and Stab control instruments went off. I checked and it threw the code "P0100". Tried replugging in my new MAF sensor, no luck. Any ideas on how to fix the CEL along with other instruments?

[Smac770]

P0100
Mass or Volume Air Flow A Circuit
MAF sensor signal 0 μs

If the sensor was reading above or below expected volume, you'd have a different P code (0101, 0102, or 0103). P0100 pretty much says no determinable frequency. The cycle time should be between 66 µs and 4500 µs (15.151 kHz and 222.22 Hz). You'd need a scope to really investigate the output signal.

You should also make sure the 5V and ground are good; if the MAF is not receiving good 5V, it won't send out an appropriately scaled output, or maybe the electronics won't work at all.

https://autoditex.com/page/maf-lab-s...orms-68-1.html
Go down until you see the Skoda (a VAG brand) 1.8 TSI waveforms. A 0V-5V square wave of different frequency for idle vs snap throttle. Idles shows about a 480 µs cycle time; snap shows maybe 180 µs.

P0100 seems to say it's just seeing DC, constant 0V or 5V, whichever it is. Could be a wiring issue between the ECM and the MAF, or MAF failure, or maybe incorrect MAF. What MAF did you get? Should be Hitachi MAF0116.

[Max B8]

Hello, I know this is an old thread but I am having a similar issue. A while back, the connector shattered between the MAFS and the engine side wiring. On the engine side, there are three wires: 12v, 5v, and ground. the MAFS has 5 wires. I had soldered them straight to each other a long time ago, and perhaps I got lucky with the correct connections because I am trying to do it the correct way and bought the connector, but can't shake the p0100, p0102 and p0103 codes. Any idea on how to wire it properly? Thank you.

[Smac770]

Assuming this is a B8.0 2.0T CAEB engine? The wires are green on pin 1, brown/blue on pin 2, and black/violet on pin 3.

Audi doesn't elaborate on if pin 1 or pin 2 is output signal vs sensor ground. But pin 3 is term 15, ignition on 12v. If pin 3 to ground doesn't measure B+ when the ignition is on, did you check the fuse 3 in the ECM box?

To verify the green wire and brown/blue wire, you'd pull the 94-pin plug off the ECM and confirm the green wire from MAF plug pin 1 to ECM 94-pin plug pin 23 is continuous, low resistance, not reading any voltage to either jump start post. And then the same for the brown/blue wire, from MAF plug pin 2 to ECM 94-pin plug pin 65.

But that Bosch ECM can be funny about MAF errors too, popping MAF codes when the problem is some other circuit on the ECM. There are no other codes or issues at the time?