Hooked the car up to the vag today, got three codes.
P1138:?
P1136:?
P0455: (Large) Leakage Evap Emission Control System Leak--I Think that was because my gas cap became faulty and the tank wasn't pressurizing properly, in fact you could here pressure escaping when the car was on if you were standing next to the cap. So I replaced that, could that have been it?

 

P1138 Long Term Fuel Trim Add,Fuel,Bank2 System too Lean
P1136 Long Term Fuel Trim Add,Fuel,Bank1 System too Lean


You are right on the money! Just clear the codes out and see if it comes back. If it does, the first two codes would lead me to suspect a faulty MAF.

 

Jestnomen, good call, 1136 and 1138 are the two I had when my maf failed.

 

Well took it to a guy I know at this garage, isn't sure what the emissions problems are, says the MAF is reading out good voltage levels, so I don't know. He did discover on top of this emissions fiasco that my valve cover gaskets are leaking. Is this a big job, or should I just leave it to the pros? This other place is quoting me at like $419 out the door.
.

 

did you take your car to someone who is familiar with Audi's?? That Evap code is almost always caused by not having the cap on tight. you may also have to replace the seal that goes around it too. The MAF problem can be sporatic (mine was). Fine sometimes and crummy other times. Go buy yourself a VAG-Com and clear the codes, and then see if they come back. i think ECS sells a valve cover gasket kit.

 

CCGIANTS, the valve cover gasket is not that big a deal. I'd say save the 400 bucks and go at it yourself. I did mine this summer. It took about 2 and a half hours, with several interuptions. When you do the valve cover gasket, you'll also want to do the cam timing chain seal. I did a write up on these a while back, I'll try and find it in the archives.

 

Yeah I just looked it up, that will definetly help. I'm just going to do it myself and save a little cash. Concerning the emissions problem, I'm going to get it smogged tomorrow and see if I can diagnose it that way. I'd go to a dealer, but its about an hour away and got too much stuff going on to be without a car for a day.

 

Also, the mechanic mentioned the possibility of the O2 sensors or the fuel filter??

 

Usually both O2 sensors don't go bad at the same time. Normally you would either see P1138 or P1136. But it could happen. I would put the fuel filter at the end of the list. But they are reletively cheap to change, so it wouln't hurt.

So are you going to do all the maintenance yourself, or just the gasket?

 

What car is it and year? I have these same codes and it was the hose that connects to the check valve and the other hose is the one that connected to the manifold.
I do have a 2001 A4 1.8TQ AWM.