Well, realize that my car has 170K on it ('95 GL with a Zetec) but it started the steering wheel idle vibration before 100K. My AC compressor is out, so I bypassed it with a non-AC belt.
When the AC did work the car vibrated like crazy! It's not bad now, but it still bugs me! At least it is a SMOOOTH vibration!
The engine can't idle much smoother actually.
I have just done a MAJOR tune up (everything if you've read my posts.) Even a new coil pack.
Must be the motor mounts.
Danny Brown