Section 85 (Engine Controls - Tests W/O Codes): Symptoms: Vibration

WARNING: This page is about a different car, the 1995 Lincoln Continental. However, it is still accessible from the selected car via links, so may be relevant.

Check radiator cooling fan.
Check drive belt.
Check engine mounts.
Check crankshaft vibration damper.
Check transmission.
Check tires and wheels.
Check driveline components.