I bought a 2000 1.8T Frw Audi A4 from a crappy private dealership, it has 88k miles on it and the carfax report shows that it was serviced every 5k miles by an authorized Audi dealer. It had a check engine light when i got it but i figured it was nothing major since it looked like it was well taken care of and pretty low miles and the car drove and idled perfectly(i paid 6300+tax, good deal huh? even if i have fix a few things..) I noticed that when I unscrewed the gas cap it didnt make a "pshh" noice cuz of the vacuum so i thought it could be one of the problems. Well I took it to Autozone right away and the code was:
Definition:
EGR system fault
Explanation:
The ECM has detected too little flow on the EGR system
Probable Causes:
1. blocked passage on EGR system
2. Failed EGR Valve
3. EGR solenoid faulty
4. Failed EGR pressure pensor aplicable
5. Failed EGR position sensor where applicaable

I also took it to my mechanic right away and he got kind of different results:
Air Injection System: Incorrect flow detected
Mixture adaptation: system too lean
Multiple cylinder: Misfire detected.
Fuel level: too low.

Then I took it back to the dealer just to see what they would say and they agreed to fix it, which kind of surprised me... They changed the EGR valve/sensor and gave it back to me but the check engine light came back on after I drove a little. I just changed the gas cap and this one makes the noise but I didnt wait before I took the car to autozone because I still dont think that it is what is causing this, maybe its contributing to it.. So here is the code I got with the new EGR:
Definition:
Long Term Fuel Trim Add. Fuel B1 System Too Lean
Explanation:
Failed MAF
Probable Causes:
1. Low fuel pressure
2. Vacuum leak on engine
3. Failed H02s

I am a little confused, but I think that the EGR was the main problem and now its something minor that is causing this, am I correct? Help me out guys because it seems like I am on my own now because the dealer is avoiding me after I called and told them I still got the check engine light. What do you guys think is the problem? what should I do or check?

 

When my 99.5 2.8 started with CEL and EGR codes, it ended up being nothing more than deteriorated hoses at connections. I replaced four little hoses (5-6mm diameter)and it all went away. With mine if I cleared the CEL it took a day or two for the light to come back on, but an 00 with 88k could use new hoses anyways.

 

Which hoses, I dont think that hoses would cause the low amount of fuel in the engine.