I have a 2004 Pontiac Vibe, and I’ve been having a problem with vibrations in the car frame. Two separate mechanics diagnosed the problem as worn engine mounts, so I replaced all three, but the problem persisted. I brought it back to the shop, and they (re)replaced one of the engine mounts, saying the problem was that the rubber inside was too dense to properly absorb vibrations, and tweaked the alignment for all three mounts. They gave me the all clear, and yet the vibration started up again on my ride home. ARG.
The vibration is coming in through the seat, the steering wheel, and the floorboards, both passenger and driver side. I haven’t personally tested the back seat, but I would assume it’s vibrating back there as well. This occurs mainly when I am at a full stop at a red light. No vibrations when I first turn on the engine, and none while it is in motion. The longer I sit at a light, the worse the vibrations get. They also seem to get more intense the longer I am driving. Any ideas?