audia6fan

Was there ever any resolution to this problem? I'm experiencing the same issue. From the threads I've read a lot of people point to the TC but I've only seen a few that have had that end up being the solution.

raj99

I believe the OP was able to fix the issue and it was due to a bad throttle body.

wtmmm

Yes, Raj is correct, after spending tons of time, energy and money trying to fix the surging the local VW dealer diagnosed the surging problem as a bad throttle body. I bought a used one for $70 and that finally fixed the problem after 18 months and an embarrassing amount of time, money and energy.... but I repeat myself.

The original throttle body itself looked fine but the electronic components were probably bad. The TB had been cleaned and adapted a number of times. We speculated that possibly spraying cleaner on the butterfly of the TB could have somehow damaged the electronic components if someone didn't do it properly. Who knows.

audia6fan

Thanks for the response...it was exactly what I had hoped for (although I'm sorry to hear that you had to go though that mess to find out a $70 part fixed your problem). I've had similar experiences with "professional" mechanics and eventually got tired of throwing money at the problems. This is why I now do all of my own work on my cars.

It's funny you mention cleaner. With some regularity I've been using the BG induction system cleaner to help combat the carbon build up on the valves. It makes a huge difference in how well the car runs but I wonder if it's had some adverse effect on the throttle body. I've got a throttle body sitting on the shelf. Hopefully that'll fix my problem too.

Jimingle10

Yes I changed mine when I did the timing chain job. Surge is gone. It is the lockup inside the torque converter that goes. Rebuilt one's are not that expensive but the labor will get you. Good luck

KevinGary

I also did the same thing and it did fix the surge.

audia6fan

I changed the throttle body and it fixed my issue. Sounds like we have a couple of possible solutions to like symptoms. For those that may follow, changing the throttle body is a 30-45 min job max and should run you $50 or so for a used part. Eliminate this possibility before doing the torque converter.

wtmmm

That is great to hear. Glad it fixed your surging issue too.

das60

Let me put a vote in for throttle body and not torque converter. I have had a 200ish rpm surge for the last few months coasting down hills and under light load. Dreaded the repair because a lot of people pointed to torque converter & transmission. I called Sonnex to ask if one of their "Zip" kits would do the job and got a firm "No" and nor could they relate my symptoms to the transmission or torque converter. They have super helpful customer service types available by phone.

I had to replace the right side DRL bulb today and since I had to move all the air cleaner bits, I went for cleaning the throttle body and a new adaptation.

RPM surge is gone. Oddly, the back side of the throttle body seemed pretty clean or at least cleaner than the DIY's i used.

Jon6373

I had a surging problem at low revs in high gear, went thru various tests back and fore to audi dealership etc.
i then had the transmission filter and oil replaced and the problem went away completely.
Audi say that the transmission fluid and filter are good for the life of the car, however ZF the transmission builders say 75k and then change both.

Hope this helps.