Brett911c4s

Hello-

I just had my engine mounts replaced and I still have a vibration in the steering wheel. It’s amplified when the air conditioning is on. I did go with the function first . See below pic. Any idea why the A/C causes it to be amplified?

Petza914

Title says "at idle", so the steering wheel is vibrating even when the car is stationary and the engine is just idling?

If so, that's very unusual. Did it do it before the new motor mount installation?

The A/C makes it works because you have another accessory spinning on the serpentine belt - well, the pulley is always spinning, but with the A/C on the clutch on that pulley is engaged and turning the compressor, which is adding load.

This shouldn't be the case. Any codes for misfires?

Get a Durametric or similar and look at Actual Values and select Misfires for all 6 cylinders. If you don't see anything being logged in those, unselect those and select engine roughness for the cylinders and see what you see there.

When you're driving, can you feel it also, or only when the car is sitting still at idle. It's possible those stiffer motor mounts are transmitting vibrations to the entire car.

If you open the engine lid while the car is running does the engine look like it's wiggling back and forth or sitting still? The motor mounts have that square end on them that needs to go into the square slot on the engine carrier bracket. If they're not aligned, the engine carrier won't actually be all the way up onto the mount so could be moving or vibrating with the engine running.

Phrog Phlyer

It could also be one of the front radiator fans. I have been told by techs at the dealership that when one or both of the fans gets old/worn out bearing they can wobble and cause a vibration up thru the steering column. When the A/C is on so are the front fans.

OKB

is it a pdk? do you have any mods like exhaust? There is some vibration with that combo.
Could be the age; does mean you need mounts. But there is some inherent vibe with pdk
There is some upgrade mounts from porsche

parhouse

Hey, I replaced my motor mounts yesterday with the same mounts from function first. My 2011 GTS manual with 27k was vibrating the whole interior when warmed up and stopped at a light. Thought these mounts would be a good compromize. When I finished changing, took for a spin. The vibration was gone accept for the steering wheel. Was even more noticeable.I think I'll give it some time and miles. It also felt a bit tighter and more responsive.