My mechanic said my motor mounts needed to be replaced too. What he told me was that the rubbers that held the mounts together wore out. My car vibrated when idle and turning on AC. The vibration happened when my car had about 45k miles.

I took my car to an Infiniti dealership before bringing it to my mechanic. The dealership told me it was the fuel injection system. My mechanic cleaned it but it didnt help at all.

 

While certainly suspicious, instead of second guessing the diagnosis, why not go all in and look at this as an opportunity?

http://www.z1motorsports.com/z1-prod...tf8dcvbl2fof53