I've been trying to help my buddy out with his new 2003 A6 Quattro 3.0 that he just got with 130k on it. We first changed out the brakes and the evap solenoid and now the car is taking an enormous effort to accelerate. We have rechecked the brakes and they are not sticking and I switched back to the old evap solenoid and that did not help either. I have also cleaned the maf sensor and that had no effect either. Basically if you are sitting still and try to go you have to pretty much floor it to begin going, but after you get above 20mph everything seems to be fine. I don't know much about Audi's I was only supposed to change the brakes and now we are having this issue. There are two other check engine lights for both cats and the egr, but I don't think they would have this effect on the car. Can anyone help me out with this? Thanks!

 

Clogged cats and egr issues that could potentially clog the cats would definitely affect acceleration. If a straw was slightly clogged and with light breath you couldn't blow through it but with stronger breath you could pass air through without neccesarily dislodging the clog. That's one possibility another could be e-brake strings sticking or binding?? But for sure clogged cats affect performance

 

Is it manual or tiptronic

 

Yeah I was going to pull the cats off and look at them and get then changed, it does seem like it is struggling to "breathe".

I don't believe it is the ebrake sticking either because when you put it in reverse it goes just like normal no resistance at all and the car is easy to push on neutral.

It's a auto tiptronic

 

Here is a video of it. This is about half throttle from a dead stop.

http://i178.photobucket.com/albums/w...ps0d2a1613.mp4

 

Abs n flashing brake light are you sure everything is straight with the brakes cause its looks as if not by mil lights brightly glaring at you check the fluid levels and make sure all the wheel speed sensors are operating correctly as these can cause those lights n also some seriously nutty braking characteristics also I still think after that you may have the acceleration if so it might be time to replace the cats as a faulty egr valve would cause contamination at the catalytic converters which could cause innefficiency which can cause failure try removing the o2 sensors if it stops then that is your problem replace the cats if not then your brake job may have some unfinished business with you

 

Car needs a new and module as well or the rebuild kit. The abs light was flashing before when the car was running normal. I told him to order a set of downpipes with cats on them because that is probably contributing to this issue.

 

Keep us posted if the DP's solve the issue or not n how the brakes are performing

 

have you tried to seafoam the intake those get clogged very easy. also look for vacuum leaks which make it run rich

 

My 01 A6 4.2 had a very similar issue but the abs and ect lights would stay on when the car was in gear. Acceleration was difficult from a stop or near stop but fine once the car was highway speeds. I changed out the brake light switch and the problem resolved.