check engine sign 01 jetta

Hi,
I have jetta 2001 1.8t automatic. Check Engine, ASR, and EPC lights is constantly on. I have spent over 2 thousand dollars at dealer trying to fix this problem, I have changed, O2 censors couple times, changed spark plugs, belt tensioner, mass airflow censor, fuel pump relay, etc.
The problem still exist and getting worst. rightnow the Idle is way off and car cough alot. gear doesnt shift smoothly and there are times, the fastest I can drive is 20mph no matter how much I try.
the trouble codes that still shows up
P0172 System too rich
P0171 System too lean
P0221 undocumented

Please any suggestions. I am really tired and broke spending countless $$ and yet problem is not solved.

Throttle body almost for sure, it at least needs to be cleaned and then re-adjusted. Also sounds like a bad cat. Sorry dude... new cat will run $1200 at the dealer ($500 if you get a recertified) and a throttle body I've never found for less than $700. One of the pro's should give you the advice any minute that either calls me a fool (it happens) or they'll say "yup, sorry" (or something like it)

Throttle body almost for sure, it at least needs to be cleaned and then re-adjusted. Also sounds like a bad cat. Sorry dude... new cat will run $1200 at the dealer ($500 if you get a recertified) and a throttle body I've never found for less than $700. One of the pro's should give you the advice any minute that either calls me a fool (it happens) or they'll say "yup, sorry" (or something like it)

Dont worry your not going to be called a fool, the throttle body would explain why the car is coughing and why the idle is off. As far as the gears not shifting properly and you not being able to go past 20 mph could be due to a bad ECU. Your ECU might be restricting your speed because the gear programing is off and must be readjusted. you might need to get a new ECU and get your tranny tuned up because the compuer threw it off.

Another item you might want to check is the metal airscreen inside the airbox. It might be clogged and restricting airflow to the engine. It sits below the air filter. This problem can result in system too rich/too lean error codes too. Just a thought.