Hey all. I have had a high idle (1200RPM when warm) and went to adjust it today, so I started by warming the car up, then disconnecting the IAC and as soon as I pulled the connector the car shuts off, it does not sputter or slowly die it just shuts off like if I turned the key off. Any ideas why it would do that?


My setup is a turbo B18C with hondata S300 ect.

 

Try giving it some throttle by hand when disconnecting the IACV. Slowly release the throttle.

 

It "should" idle at like 200rpm.

 

The base idle with the IACV disconnected is 450 +- 50 RPM.

 

I always knew it as around 200rpm. My mistake. I guess I should go adjust mine to.

 

Clean it before you adjust the idle.

 

Stock Idle for my engine is 750rpm +-50 according to haynes, and rpm is supposed to drop about 100rpm when the IAC is disconnected. I really do not want to pull the IAC off if I don't have to, I was hoping there was something I was just missing. According to haynes if I disconnect the IAC and the RPM does not drop at all then the IAC is probably bad. However is says nothing about the car shutting off when disconnecting it, if anyone has any other ideas let me know, if not I will assume there is a problem with the IAC and go ahead and pull it off.

 

Try starting the car with it disconnected. I recall my car stalling when setting the base idle. You have to slowly release the throttle and let it idle. Then you adjust the idle screw.

 

I have a similar problem with my ITR swap, its never done this before but now i have a high idle on cold start up at 1,400 rpm it drops as it gets warmer but it always had a lower idle on cold startup and theres no real change in temp here.. is my IAC going bad??

 

Does it idle like normal when it warms up? It's normal for the idle to be higher on start up but not after it is at running temp. According to Haynes the B18C5 (ITR) is supposed to idle at 800RPM +- 50RPM when warmed up.

 

I'll give that a try next.

 

op sorry for thread jacking at least its one less thread, it idles fine at warm up,, only thing is it used to idle way lower on a cold start up! now it starts at 1400rpm i recall it at 1100-1200 then when it warms up it was normal. i have no real change in temp here.

 

Oh ok, that's not a huge change. Are you throwing any CEL's? I'm thinking maybe it could be the 02 sensor but that would throw a code if it were bad.

Also maybe try to think of anything you may have changed in your setup since it started doing that, it may be something you added or changed.

 

Thats what i thought too, i put my buddy club cat back back on and the secondary o2 is removed so theres a cell, but it never idled that high after the change maybe a few weaks later. maybe i should check the cell and see if its something else that was added to the code list.

 

I bet that's it, makes perfect sense. Besides 1400 when completely cold is not very far off anyway, sounds close to normal. Or if it bugs you, you could always check what engine codes it is throwing specifically by putting a jumper in that little plug under your dash and counting the blinks of the CEL, For instance 2 long blinks followed by 3 short blinks means it is throwing code 23 ect ect. Have you ever done that before to check engine codes? If you haven't I can give you a link to show you how, it's super easy.

 

Dude thanks allot! yea i know about that trick, i had my friends actron scanner but i gave it back, im just gonna run the codes one more time and see whats going on, i know my car so well and i know theres a issue cause of the strange higher idle.