[ExCrystal]

Long story short: car was at the dealer for 20 days due to an airbag sensor failure. Picked it up today, and my car was shaking/shuddering while at a stop. Not sure if it does it while moving.

Asked my service manager if it’s normal (I’ve read and asked about the A8 shudder problem on here), and he said drive it for a bit as it’s been sitting.

Should I worry? I’m going to drive it for a few days or so and see if it goes away since the car was not driven for 20 days. Car wasn’t shuddering or shaking before dropping it off. Thoughts?

Thanks!

[RunRS9114]

Hey ExCrystal. I had my SS in the shop for a couple of weeks getting some damage repaired from a kid backing in to my car. I had this same issue on the drive home from the body shop. I took it out for a 15-20 minutes drive afterwards and the issue went away and hasn't come back (this was about 2 months ago now). I think the LT engine just doesn't like to sit for extended periods of time or maybe they disconnected the battery for a while and it has something to do with that. Someone more technically inclined may be able to chime in!

[ExCrystal]

Originally Posted by RunRS9114

Hey ExCrystal. I had my SS in the shop for a couple of weeks getting some damage repaired from a kid backing in to my car. I had this same issue on the drive home from the body shop. I took it out for a 15-20 minutes drive afterwards and the issue went away and hasn't come back (this was about 2 months ago now). I think the LT engine just doesn't like to sit for extended periods of time or maybe they disconnected the battery for a while and it has something to do with that. Someone more technically inclined may be able to chime in!

That's what I figured, too. No issue during or after my evening commute, though I did feel and head a weird vibration under slight acceleration while going up a slight grade on the road. When I'm pressing the gas lightly to go about 10-15 mph, I also hear a slight purr--not the purr of the v8! lol

I don't know - maybe it's paranoia, but I'm gonna give it a few days before I think about this further.

[Cameron27]

..

[arpad_m]

Originally Posted by ExCrystal

That's what I figured, too. No issue during or after my evening commute, though I did feel and head a weird vibration under slight acceleration while going up a slight grade on the road. When I'm pressing the gas lightly to go about 10-15 mph, I also hear a slight purr--not the purr of the v8! lol

I don't know - maybe it's paranoia, but I'm gonna give it a few days before I think about this further.

I also get this occcasionally (and never did with the previous V6 Gen6). Right now my lay guess is it's panel vibration caused by the V8's resonance happening to be the same as the eigenfrequency of a body panel at a certain rpm. Perhaps the reason we can only feel it going very slowly up an incline is that otherwise it gets suppressed by tire/road noise.

(As a side note, this is still nowhere near as bad as the clunky 3->1 downshifts I had with the A8 in the V6 under similar circumstances, which is not happening at all with the A8+V8 combo, this 8L90 specimen looks better so far.)

[camaro5]

The battery was disconnected for an extended period of time clearing the PCM VRam, so the PCM has to relearn its parameters outside base programming.

k

[init4fun]

Originally Posted by ExCrystal

Long story short: car was at the dealer for 20 days due to an airbag sensor failure. Picked it up today, and my car was shaking/shuddering while at a stop. Not sure if it does it while moving.

Asked my service manager if it’s normal (I’ve read and asked about the A8 shudder problem on here), and he said drive it for a bit as it’s been sitting.

Should I worry? I’m going to drive it for a few days or so and see if it goes away since the car was not driven for 20 days. Car wasn’t shuddering or shaking before dropping it off. Thoughts?

Thanks!

Mine did this when I first took it out of storage. Actually thought the gas had gone bad but it had only been sitting for 4 months with a full tank and a full can of Seafoam in the tank. It cleared up in a couple of days. Actually it cleared up the first time I got on it hard but that took a couple ofdays as it was still cold in my area.


If they disconnected the battery for any length of time that could cause it as well .

[ExCrystal]

Thanks for the replies and insight.

She's doing well for the most part. I still feel the car rumble a bit while driving only. Seems to be around 25-28 mph, going down a slight incline with a little pressure on the gas peddle.