ive had this engine idline problem before in a previous civic i owned... the idle jumps from apx 1k - 2k... and them sometimes it will die down... i figured out the problem along time ago but now its like im a noobie again since i been out the scene for so long. also i was using nos before, and now its a turbo setup and the idle revs up and down... any ideas folks? i tried to mess with the idle on the throttle body but that didnt seem to help.

im running a normal turbo set up with a chipped p28 with a p30 map, obd1 conversion, vortech 11:1 fmu, stock injectors, 255 fuel pump, the usual goodies.

 

the problem is most likely the Fast Idle Thermo Valve. this is located directly under the throttle body. to fix the surging you will need to remove this from the car, and on the part closest to the firewall, there is 2 8mm screws, unloosen them, and inside there is a white plastic thing, just tighten it up with a flathead screwdriver. than reinstall the cover plate. and put it back on the car. besure to replace any "lost " coolant. goodluck,