01 jetta diagnostic problems

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
now dealer recommend replacing TCM $600.00 apr cost
Please any suggestions. I am really tired and broke spending countless $$ and yet problem is not solved.

check the pcv and breather lines. Its the large 1in piple that goes from the intake pipe (a circle valve) to the valve cover, then under the intake manifold to the block. they are a common failure arround 50-70k miles on 1.8t. its about 500.00 for parts (new thicker rubber pipes last longer) plus install. they will look like theres oil on the breather lines or wet dirt