Whenever I start my car from cold it will idle at ~3k for a minute, then it'll spike from ~1,500 to ~2,500 rpms until it's warm when it has a steady 1300rpm idle. I know that's high, just wondering what the surging could be coming from. The IACV is new and it didn't have this problem before, so I don't think it's the tune.

 

Check for a vacuum/intake air leak. Any CEL codes?

 

Check what he said then if that dosen't do it its probably you iacv if you use break cleaner and take it off the back of the manifold you can spray it out and it drys fast start it back up and see what happends

 

Not that I can find, and no CEL, but when I check for codes I get some traction control **** that's for JDM ECUs and #20 electrical load detector. No clue what that is.

IACV is new and I've tried multiple others just in case that was the problem somehow.

 

bump[

 

What engine? Do you have an FITV?

When the idle is high or fluctuating, pull off the intake and then use your finger to cover the hole leading to the IACV in the throttle body. Dose the idle drop and the fluctuation stop?

Have you bled the cooling system?

 

It's an LS VTEC no FITV. I bled the cooling system when I replaced the thermostat. Is there another hole in a B16 throttle body to the IACV? I thought they were only in GSRs for the dual butterfly.

 

Covering up that hole had no effect on the high idle or fluctuation.

 

get a can of intake cleaner/ carb cleaner and spray it around the engine bay with the car running. when you hear a pitch change (bogging sound) you have found your vaccum leak. and have you ever tried clocking your TPS?

 

do you have the correct plugs? gapped right?
what about the rotor and cap electrodes? are then clean?

you burp and bleed the coolant all the way?

 

There's no vacuum leak, and the TPS is stock it shouldn't need to be clocked in should it?

Yes plugs are correct and gapped, cap and rotor were replaced a couple thousand miles ago because I thought that might be a problem. Coolant was properly bled all the way.

I honestly can't think of anything else it could be, I even swapped out my chip into a different p28 that I knew was 100% working and it still did it.

 

mine was a stock TPS and it needed to be clocked to correct my idle problem.

 

i can not remember the exact voltage but i think it need to be .47 or .48 volts at idle. somebody correct me if im wrong please

 

Alright, I'll go hook up the voltmeter and report back.

 

gl