Hey everyone, i'm currently new to Honda-Tech and I am having some idling issues. I have searched and searched and searched for the solution, but noone is having the same problem as I am. I have a 98 Civic Hatchback with a GSR swap. It has been a little cold here in Missouri and my car has been idling high when first started up, around 2500rpms, anyways, but the other day I drove it a little hard and after it warms up, it surges from 1300-1500 for a bit then finally it only drops to 1100rpms, instead of the usual 750-800. I cleaned the throttle body and nothing changed, tapped on the IACV and nothing changed also. I unplugged the TPS sensor and the car revved higher, so I know it's good. I unplugged the MAP sensor and the car died, so it's working as well. Then I pulled off the radiator cap and let the car run to make sure there was no air in the coolant system. Does anyone have any more ideas to what the problem could be? Maybe the Fast Idle Control Valve? I also havent checked any lines for vac leaks. Or could it possibly be a bad thermostat? I drive 25 miles to work and let my car idle 7 minutes before driving it and by the time I get to work, the car is only on the Cold LINE!. Could it be an ECT sensor? Like I said, i've searched anc searched. Any help and feedback would be greatly appreciated! Thanks everyone.

 

Nevermind, I fixed it. I pulled off the IACV and cleaned it and still rev'd awful.. So I pulled off the tb and cleaned the FITV and then tightened it up and that was the problem. So if anyone else is having this problem. I strongly suggest you look into th Fast Idle Thermo Valve first. My car went from idling fine one day to sounding like crap the next. Thanks!

 

Im haveing the same problem on the same car same engine But i have something else going on when you steped on the car to high revs mines maxes out a 7000 rpms i was wondering if you had the same problems before you fixed if so i would love the help thanks

 

No I did not, my car drove and rev'd to 8500rpms without a problem. Never stuttered or anything. It was just acting crazy at idle. I hope you figure out what the problem is.