My car was shuddering as I drove it and it turned out to be an assortment of issues. 1. Replaced all 4 tires. Helped for a bit. 2. Replaced the distributor, coil and ECM as it was stuttering in idle. Not much effect. 3. Had it tuned at a tire store place- they moved all of the wires on the distributor cap around one to compensate for the fact that they put the distributor in 1 tooth off. FAIL! 4. Had distributor moved over one, the car tuned and wires corrected by an older fellow with a mobile service. Now the car idled correctly. 5. Replaced the front bearings. Rotors were deemed "OK." They weren't. 5a. Went back and they replaced the rotors at no charge. Much appreciated. These things start simply enough....and evolve from a "task" to a "mission" to a "quest!"