I have a 1993 850, manual transmission, 86,000 miles, that has sudden low idle, then after the car has warmed up, pulsing idle between 750 and 1000 rpms. In addition, the acceleration periodically surges to 4500 rpms and there is a slight feeling of skipping when in 3rd gear. All these issues can be temporarily (10 - 15 minutes) solved by shutting off the engine and restarting the car. It's been two mechanics, 18 months, and over $1200 and the problem still is as bad as ever. These are the repairs that have been made so far:
1. Vacuum hoses replaced
2. Ignition wires, cap, rotor, spark plugs replaced
3. Cleaned throttle plate - twice
4. Replaced cam position sensor
At this point I believe that the mechanics are just guessing on my dime. Has anyone else experienced this? I'm frustrated to the point of selling and becoming a Toyota owner - help!