Subject: 2001 A6 4.2

I have been having some jerking, or stuttering when accelerating or under slight load, such as going up a slight incline, the RPM's tend to be between 1700 to 2000, once I accelerate it to the 2k mark it goes away, when cruising down the highway I have no problems at all, I think it might be a vacuum leak of some kind or an air/fuel issue, (or could it be a tranny issue) but I have not been able to locate it. I have no codes. I replaced the MAF recently but it did not help.

also I replaced the plugs, fuel filter, air filter, cabin filter, battery, timing belt, and all the accessories in the front of the engine such as the water pump, pulleys, other belts, thermostat, about a year ago.

any advise would be greatly appreciated.

 

I would have to ask if you have any fault codes stored? , check engine light on?
Sounds like it could be a misfire , could be a bad inner c/v joint on the axle , torque converter.
Just guessing!

 

I have a 03, 4.2L and had the same problem. Did a timing belt change and the mechanic discovered that both of the manifold intake linkages were broken. They are made from hard plastic and break easily, had them replaced with aluminum type and the problem is gone. Car is running smooth now.

 

My wife's A6 avant had the same symptoms and eventually found an error with #6 cylinder misfiring. It was. It as straightforward to find. This was a 6 mos. process and it stopped after replacing the cord, dealer said the plugs were fine. I'm going to replace the rest later.

 

Solution found! Yah! It was after replacing the coil pack and plugs that the jerking stopped.
Thank goodness I thought it was the transmission which would of cost an arm and a leg.

I would like to also mention that along the way to this fix and visiting many forums I had replaced the following items: all: Vacuum lines, MAF sensor, and the CV axle shafts.

Also the linkages were replaced when I first purchased the car it seems to be a common problem. as you mentioned the plastic ones break easily, I also had them replaced with aluminum type from GruvenParts.com

Although these items where not the fix to my problem it was probably time to change them anyway since the car is a bit older (its a 2001).

Thanks for all the feedback hope my experience help someone with this fix