Okay guys desperate here....

1996 2.8L A4 Quattro 12v manual.

CEL on, ECU reporting lean codes from banks 1 and 2. Car is no doubt not driving like it once did.

Now I know it could either be an oxygen sensor, a fuel injector, an vaccume leak, or a sensor.

I've tinkered and concluded the following....
1. It cannot be an oxygen sensor...if it was only one bank would be operating lean correct? (Both Pre-cat O2 sensors replaced recently)
2. It cannot be a fuel injector....same logic as before that injector would only effect one side of the engine
3. It cannot be a vaccume leak.....i've replace and inspected all the lines
4. It cannot be a fuel dilvery problem, when I disconnect the connector going to the MAF sensor....the engine defaults to a rich operating state as it should (engine runs nice and smooth during this state) ruling out any fuel dilivery problem

That leaves me to conclude it's either a bad MAF sensor or some other kind of sensor on the intake side of the engine. I have cleaned the MAF sensor with the cleaner you get at AutoZone and it's made no difference. I don't have a VAG com so I can't take readings of the output values of the sensor....but I assume the generic tire place that I normally take my car to would not have one either and just start swapping out parts until it starts working properly

Hoping somoene else has had and solved this problem before....I have little money to replace parts that don't need to be replacing but this car has to last me until I get out of college.

 

One thing I recently discovered is that you should reset the ecu every time you do some thing like cleaning the MAF sensor. Even if its with a basic scan tool.

 

been done. w/scan tool & discnnecting the battery