Transmission problem '05 A6
 

New user here in need of some help/advice.

I have an '05 A6 3.2L with 130k. Recently I was having problems where the car was surging/sputtering at light loads, especially when cold, but it didn't sputter during acceleration. I saw some posts here about the possibility of throttle body and torque converter. My local mechanic cleaned the throttle body and that did help for a while but then the problem came back and it became so bad I finally took the car to the closest Audi dealer who cleaned the intake valves for about $1,300. They said the valves were very gummed up - strange for a car like this, especially since I have always filled it with premium gas. Anyway, that fixed the problem and the car even felt quicker.

However, I experienced something else today that seems very bad. I was driving in the "S" sport mode and all of a sudden the car started to vibrate and shake in the front. Initially, it felt like a suspension issue but I quickly noticed that it only happened during acceleration, not when coasting or barely giving it gas. Also it did vibrate bad when I revved the engine in neutral. After I got home and stopped, I started it up again and noticed that the transmission light was on.

Any thoughts? Does this sound familiar to anyone? I'm hoping it is not a bad transmission.

Our cars have a transmission light? has the ATF ever been replaced?

Engine Problem (not Transmission Problem)
 

Kevin, thanks for the response. I realized a couple of things that were wrong with my assessment. First, since vibration happens when in neutral, it probably isn't the transmission. Second, what I thought was the "transmission light" is really an engine light. In summary, I'm an idiot.

That said, I'm afraid this is really an internal engine issue related to when the dealer took of the intake manifold to clean the valves.

Looking at another post recently, I wonder if this could be related to the timing chain since I am at 140k?

btw, this forum is great. Wish I had spent more time on it earlier.

If it is the timing chain I would think that you would have the timing chain rumble at start up. Do you notice any strange noises at start up?

KevinGary, nope, the car doesn't make any new rumble our sound at startup. I just started it and did hear the normal odd rattle that has been happening with cold starts for years (dealer checked long ago and told me what it was but I can't remember).

The car idles fine in neutral and park but when I give it gas, the engine starts to shake and vibrate pretty bad, worse at higher rpm. I don't want to drive it. Could just be misfiring from a bad coil or plug, or maybe worse.

I probably need to get the Vag-Com that everyone talks about. Is there a particular one that works best for Audi's?

your probably jump a tooth on the on the timing sprocket, there is only one real VAG-COM, the others are Chinese copies. When you get it, check engine measuring blocks 91, 92, 93, those values will tell you if the engine control module is compensating for a jumped tooth, to be honest it definitely sounds like, hopefully for you I am wrong

Newa6er, thanks for the response.

Yeah, maybe it is something else, a scan should tell a lot.

If it is the timing chain or if my car will need that at some point, what is an estimate for that repair? As I understand, the timing chain can just go bad around 150k (I have 140k) or these cars can just drive and drive without any issues. I saw the post where odoboyusa showed doing the timing chain on a rebuilt engine @ 161k.

If it is the timing chain, is it possible that I've done some damage by driving it after the problem started? It seems like the engine idle would be rough if it caused some damage but engine is fine at idle.

the audi v8 is an inference engine, which means that the valves and pistons can come into contact with each, if they do, only bad things can happen, I have not read much about a tooth jump causing a valve/piston collision

at 140k you should get a vag-com to help keep her running. ask if any one is local to you wth a cable they can scan your car. Also is it safe to assume you have kept up with all maintenance, filters spark plug coil packs recall, trans fluid change?????

I am from Bergen county as well