WSP2001

a couple days ago I posted some questions... I got one response that said 'your car is under
warrantee, take it to the dealer....' I KNOW my car is under warrantee, I AM taking it back to
the dealer... my questions for you guys were just trying to determine if anyone else had these
type of problems...

1 - rough idle, whether the engine is warmed
up or not, every once in a while the car will
kinda kick like a compressor's coming on, but everything is turned off...

2 - rattle from somewhere under the hood driver's side when I shut the car off...

when I had it in the first time, the service manager said he wanted to get a car with similar
miles and check to see if my car was 'normal' compared to that one... I seriously doubt that
that nasty idle-shudder or the rattle are normal for a $30,000 car, but I was hoping you guys
could give me a little more constructive feedback, even if it was nothing more than 'no,
that's not normal, tell the dealer that...'

Bill

WJM

Here are my best guesses"

1:stumble -misfiring cyclinder... Check coilpacks

2: Driver side? this one stumps me the most... I have no idea

KenK in TX

...but its only happened two or three times and it was very slight.

Can't say I've ever hear a rattle of any sort from mine. Can you be more specific about what the rattle sounds like and whether it does it all the time? (Is it metal tapping metal, plastic on plastic - you know)

md_audiA4

my car has a rough idle as well. Sounds like we have the same problem except i have the 1.8t. It feels like a big truck is pulling up next to me when i am at a light but there is nothing around. I know this cannot be normal because i didn't notice 3 months ago, but i notice it at just about every damn stop. My dealer hasn't been able to find the problem either. Replaced my spark plugs and seemed to help a little but no where near what the car used to be.

WClark

That seems to have been related to a "flat" spot on the AC compressor pulley.

Every once in a while I hear a "rattle" when shutting off or starting up, for just a moment and I assume it is the engine block or something attached to it touching a chassis mounted item at the moment the block jumps with the engine suddenly going from idle to stop or stopped to idle.

Kris Hansen

Actually, my car does do the same thing, but it is random. My wife's 12v does it, my old 80quattro did it, my corrado did it. I suppose it is normal to a certain extent. It is a little unsetteling, but without spending hours diagnosing the problem, I just ignore it. Until of course the one day that it stumbles, and the engine stalls or throws a MIL, then I will take the time to figure it out. On the 12v, it started stalling, and I cleaned the ICV, and the idle became much smoother, and it did not stall.

My guess is that the ICV is sluggish, or maybe it is mis-firing, but I would think a misfire would trigger the MIL.

ScottAW

The only issue I've had so far was what I think was a bad tank or two of gas causing my car to stall on a cold startup. The day before my 5k service it stopped doing it and hasn't acted up since. Ironic, eh?

Rodney

Might be a bad batch of gas (which would probably throw some codes when hooked up to a VAG tool), or could be a problem with the computer itself or perhaps the DBW control of the throttle body is going flaky and messing with the idle. Could be a number of things, but doesn't sound normal to me.

Dan F.

The 2.8 does vibrate a lot more than most other cars at idle. I don't know if this is what you mean by "roughness" but it's normal to feel some vibration in the steering column and pedals.

Also, at stop lights, mine has a periodic quirk in which the engine will hesitate for a moment (about half a second) and the lights will dim. I've never been able to reproduce this problem for the dealer and there are never any codes in the ECU.

Dan

WSP2001

my first thought was that it was maybe the gas I was using, but I've switched brands
twice since it started, always 93 octane, and I get the shudder pretty consistently,
so I'm pretty sure that's not it... it DOES feel like a compressor, but the AC's off,
so... guess I'll mention the ICV or maybe the plugs, but new plugs at 5k miles??

as far as the rattle, I've cut the car off while sitting drivers side and passengers
side, and its definitely louder from the drivers side... heh, actually, it kinda
sounds like, well, plastic-y... try tapping the up and left arrow keys on the keypad,
but lightly, not enough to actually depress them, about 2 times per key, and oddly
enough, that's what it sounds like...

thanks for the responses, guys... hopefully one day they'll figure it out...

Bill