1996 MarkIII Jetta 2.0L, I cleaned the MAF and throttle body 6 months ago to try to help smooth out a rough idle (it was staying up near 1,200 rpm). It helped at least for a little while but then went back to a higher idle of about 1,100.
Using a cheap ebay vag-com knock off cable I got the following error codes from a full scan:
(they were all from the engine section)
16555 fuel trim too lean: bank 1
P0171 - 35-00 --
16824 - shareware version etc
P0440 - 35 - 00 --
16517 shareware version
P0133 - 35 - 10 - intermittent
16486 Mass airflow sensor G70 Signal too low
P0102 - 35 - 10 - intermittent
Cleaning the maf doesn't really work well, I'm 90% positive your maf is faulty now. You can ignore the O2 sensor slow response fault code because it's due to your poor fuel trims. Pulling the electrical connector for the MAF will cause the ECM to revert to the base map which is basically the ECM putting in the values that the MAF should be reading automatically.
Have you checked for vacuum leaks, check to be sure you don't have any disconnected vacuum lines or holes in the intake boot.
I made a thread where I've been going through ideas: http://forums.vwvortex.com/zerothread?id=4226900
I haven't checked vacuum lines because I don't know how to. I did order a gas cap since I've been told by multple sources thats frequently the problem.
Oh yeah and thanks alot man!
Not a problem, I'm going to stick to this site though. I designed it as an alternative to the other sites where it's primarily hobbyists diagnosing cars. Ideally people get their diagnosis, pay $10 or pay $3 to see previous answers, and can diagnose their car without all the guessing by people who aren't techs. Also the VAG-Com guys don't like it if you aren't using their program, which is an awesome diagnostic tool but often times the car can be diagnosed using only fault codes. It really isn't necessary for a dealer tech to have a full scan.