My 2000 A4 Avant 2.8 ATQ had an itermitent stalling problem over the last month . It would die at a stop light but would start right back up. I figured a fuel filter was in order along with a bottle of injector cleaner.I changed the filter. Car ran great for a week or so, but last night it quit 3 times and the last time it did not restart. (It happened to be raining). I checked the fuses on the fuel pump and # 34 fuse for the engine controll unit. Both fuses are good, but there is no voltage present on the circuits. I used a jumper wire to the fuel pump lead in the fuse box and was able to get the fuel pump to run but still wont start. I checked the coil packs with an ohm meter and they are within specs.I also checked connections on cam position sensors ,coil pack ( no voltage present) for corrosion. Something has shut it down and I could sure use some ideas. Fuel regulator checked out ok too. How about the MAF , crankshaft position sensor, or could it be th ECU? I plugged in my OBD 2 and pulled a code P 1425 which is "Fuel tankvent valve shorted to ground" What the heck is that?

 

Thats the evap purge valve. Its on top of your airbox. You can try pinching the line to see if it will start. If you dont have power to the ecm your car definatly wont start. Figure out where you lost your power on 34 and you have your problem.

 

When it died on Thursday, the 1st we checked was the fuel delivery and it checked out ok. The shop had replaced the ignition module a few days prior because the car had a miss, and new unit failed with-in 5 miles of driving. Something is going on somewhere.