Vibration When Stopped/In Reverse

**Sauci** · 04-10-2016 03:39 PM

Just installed some new H&R coilovers on my B8 A5 8 speed quattro with a buddy. While doing the install, I pulled the axle out of the cv joint. We managed to pop it back in and thought everything was good to go. When I started the car up, everything sounded good. However, once I shifted out of park, the car started vibrating like crazy. Don't think that it was misfiring as I've felt that on these engines before. As soon as I let off the brake and start rolling the vibrations stop but return as soon as I come to a complete stop. Shifting to neutral makes them stop however, reverse also causes these intense shakes. No issues with RPMs while moving nor while idling. No CEL or an indication the car thinks anything is wrong.

I'm not sure what is wrong, but it's extremely worrying and I don't want to damage anything further by driving on it if it's something serious. Could I have damaged the cv joint while reinserting it? I can't see in there as there is boot covering it and even though it took like an hour to figure out the right angle to get that popped back in, it seemed like everything was inserted correctly and where it needed to be.

Any help or suggestions would be greatly appreciated.

**Sauci** · 05-28-2016 02:21 AM

So far, I have replaced the motor mounts, made sure the exhaust isn't touching, had the cv joint inspected and one of the boots replaced, installed a new PCV valve and nothing has worked. Ok, it may have worked slightly. The vibrations have decreased by about 40% but still much more than there should be. Seems to go away when I turn off the AC so i'm wondering if that has something to do with it.

**TTRStud** · 05-30-2016 05:50 PM

Originally Posted by Sauci

So far, I have replaced the motor mounts, made sure the exhaust isn't touching, had the cv joint inspected and one of the boots replaced, installed a new PCV valve and nothing has worked. Ok, it may have worked slightly. The vibrations have decreased by about 40% but still much more than there should be. Seems to go away when I turn off the AC so i'm wondering if that has something to do with it.

Are you positive that all motor mounts have been replaced? Better yet, have they been replaced with the OEM mounts? There are some really good aftermarket options (034) but they increase in-cabin vibrations on cars with the 2.0 engines since they tend to shake more than the larger motors.

**Sauci** · 05-30-2016 05:51 PM

Originally Posted by TTRStud

Are you positive that all motor mounts have been replaced? Better yet, have they been replaced with the OEM mounts? There are some really good aftermarket options (034) but they increase in-cabin vibrations on cars with the 2.0 engines since they tend to shake more than the larger motors.

100% positive.