I have a 93 honda civic. Recently it has been idling high then surging back and forth between 1000rpm and 2000rpm.
I have replaced my map sensor, o2 sensor, caycalic converter, throttle body, throttle body sensor, fuel lines, etc. Each time I do this it seems to fix the problem for a couple of hours then it happens again. The surging and then randomly the car will shut off while I'm driving. Check engine light comes on. I have had it coded and it comes back to the map sensor and I have replaced it 3x.

Any help would be greatly appreicated.

Sounds like bad wiring to the map sensor

. Ensure there is no air in the cooling system, by filling the radiator with coolant until it comes out the opened bleeder bolt.

. Replace the Ignition Control Module (ICM), if the problem persists. The BLU wire from the ICM goes directly to the tachometer, if you have one. This likely accounts for the fluctuating rpm. Be sure to apply silicone heat transfer grease to the back of the new ICM.