Ok so my car is driving me nuts. I start it up and the idle keeps jumping up to 2-3,000rpms and bounces back to 1,000. I know it is the way the car warms up when it is really cold, but last couple of days it keeps going even after it is fully warmed up. I know it has something to do with the some device in the intake manifold... I searched for awhile and kind of get it, but need alittle more input from you guys so I can fix the problem. By the way my mods are V2 AEM intake, Dc header, and a custom apexi WS2 (no catwith 2.25'' strait pipping from the header back) Thanks guys.

 

IACV

Clean the screen or bleed the coolant to make sure you don't have anyair

Search for the rest

 

Yeah, I agree with the previous poster. It does sound like there's air in the coolant. The temp sensor is at the high point of the cooling system -- where air bubbles will migrate. As the bubbles move under and then away from the sensor tip, the sensor reports "cool" and then "hot" and then "cool"... so the PCM keeps changing from cold idle (high) to warm idle (low) speed.

Bleeding the cooling system should fix it.

 

ok I am going out now to try that thanks. what about resting the computer?would that help?

 

You could try that? but it prolly won't work

Do you have a check engine light?

 

my lude is going thru the same problems. i found out that it is my eacu. so i tryed cleaning it and it still occured, i'm replacing the engine which is a little extreme but my engine has 215000 miles on it so you see my reason for replacement. what i was told was to replace the iacv if i wanted to keep the engine. i heard that iacv's going out on honda's isn't uncommon at all. good luck with it.

 

ok changed the antifreeze and rest the computer... still nothing. I did some researched the IACV figure its the problem. But I still need some help with where it is and how it works, so I can learn why my car has its problem. Thanks guys

 

Jus a follow-up, has the problem been fixed? It's quite possible that it could be the Fast-Idle control valve as well.

 

I have that problem because my EGR is clogged, did they have those in the early models?