kemer1

Oh I'm not knocking you for using Shell fuel. Hell these are expensive cars, so why cheap out on the fuel. I used to run nothing but Chrvron with Techron...and still do in the two cars I have now. I also used to just punch it getting onto the highway to "clean out the carbon" which only got me "yeah whatever" looks from my fiance. But it was what it was. It's sad that this awesome new technology is being hampered by the fuel that we have to use. And untill that issue is resolved I'm gonna keep away from DI cars.

gk1

My CEL came back on after the TSB. See the update.
https://www.audiworld.com/forums/sho...php?p=23939343

The G Man

I did that software update about 3 months ago, the CEL came back after a month. My dealer just did a carbon cleaning for the 2nd time in 12000 miles and this time, they change 3 fuel injectors as well, I hope that fix the problem.

2008A6

It's interesting that this problem is getting more attention recently. Wouldn't this carbon buildup be happening to every A6 sold in the last 4 years, if it's happening in cars at less than 15K miles?
And i would assume this carbon cleaning needs to be done on a regular basis for the life of the car since it's a mechanical and not software issue.
Hmmm...not sure i want to buy out my lease anymore

Anyone have feedback re: new BMW or Mercs with the same issue?

JackKrash

I have been getting these CEL's since 100 miles (now over 25K)- Everytime I bring it in the dealer thinks it's fixed - a few days later the light is on again.

It's been in for service at least 6 times for this issue, TSB's cylinder coils, spark plugs.

For the most part this car has been great (2008 A6 Avant) - but I think this is my last Audi.

gk1

This sucks. Just got the word they are doing the manual valve cleaning. Service manager states he doesn't know why it happens, but it is a common problem. He offered to let me speak to the shop foreman for a more technical answer when I go to pick up the car.

gk1

That's exactly what I was thinking. '05s have a hell of a lot more miles and don't seem to have this problem as often as '08s. What changed?

Service manager says he's "hopeful" it wouldn't have to be done again. That's not really a good answer.

spence341

My 05 3.2 has 81,000 miles. I am affaid to say this in fear of jinxing myself, but no CEL light yet. I would assume that I have some build up, but I do get on it every once and a while.

gk1

https://www.audiworld.com/forums/sho...php?p=23941094

Faelcrom

Just got the A6 back from having the CEL on a second time. The car was miss firing badly during cold start.

The first time was a few months ago, they performed TSB 2020645/5 which was for the ECM update. This time they performed TSB2019948/3 which starts with using G17 fuel additive & driving the car for 50 miles. When the problem didnt' go away, they pulled the intake manifold and manually cleaned the carbon built up from the valves.

Here are some notes. This is primarily my wife's car, she used it for long freeway commutes (over 100 miles a day) for the first 25K miles and we didn't see any problem. Since November her commute has shorten to less then 10 miles.

There have been other post tieing in with short frequent low RPM driving will promote carbon built-up. Our case certainly supports this.