1997 a4 2.8 12v---- Car drives smooth but slow to accelerate and will not go over 60mph.CEL reads an o2 sensor (which it has done in the past due tostaight pipes (no cats) BUT car ran always great. Is it possiblethat car is stuck in limp mode with codes cleared???? Will o2 fault send car into limp mode???????Tried unplugging BAT also. We ran VAG and reset codes but it still does the same thing. We have checked everything from MAF, Throttle control module, igntion system, fuel pressure, compressionetc.... Everything is good. We even tried anotherCPU. It just seems that it is inLIMP mode.Is possible to have good fuel pressure but fuel pump not working correctly as it is the only thing not replaced????????

SUGGETIONS PLEASE!!!!!!!!!!!!!!!!!!!!!!

 

what were the codes?

 

What type of tranny?
If auto, do all your gears light up in red on the dash?

 

5 speed tranny

 

no codes at this point--drove car car for about 50 miles-----if it comes up again I'll let you know right away...........

 

I did not know there was a limp mode for a 12valve maual.

Is there? I though limp mode was only for turbo models.

 

I didn't think so either but we can't think of what else it could be.

[:@][:@][:@][:@]going CRAZY!!!!!!!!!!!

 

UPDATE------my buddy drove car to gas station----after refueling, car drove GREAT through ALL gears for a few minutes until stop light, then idle went UP and DOWN several times before engine stalled. Restarted car, idle went back to normal then went back to driving like S@#T again.

 

Check the codes, there should be some without triggering a CEL. Could be dirty throttle body or lost of possibilities

 

Possibly fuel filter, fuel pump, or a really dirty throttle body, or maybe a bad injector.

Of course, you should be getting misfire codes at least. Have you checked for air/vacuum leaks, dirty TB, or tried to do TB alignment?

Anyone else have any ideas? Im no 12valve expert by any means, just kicking out some possibilities............