Saw this coming.. IAC issue?

[LKSi]

My car idles up and down continuously. If I block off the IAC port inside the TB, the idle returns to normal. I'm just confirming that I need a new one before I purchase one or if something else can cause it to be stuck open. Thanks guys.

[paton]

I can't confirm your issue, but I'm having the same problem. I got my swap fired up for the first time last Thursday. It's open header, no O2's connected and it idles up and down constantly. I've only been letting it run for about 15 seconds at the most.

I'll have to try the finger on the hole thing to eliminate the IAC as a suspect.

[wolydotmatrix]

IAC is most common. try unpluging it to see if the idle changes. Also, me and others have had vaccum leaks from unseated TB's, aftermarket plates, gaskets, hoses etc.... Double and triple check the dumb stuff before you spend your money. May also try adjusting the valve first.

IACV/RACV adjustment: for the ones located under the TB

Remove the tamper-proof screws.
instal new screws loosly.
at warm idle rotate the valve to adjust your idle.
tighten screws once desired idle is met.

If this proceedure does not help or the idle remains high or surge then you got bigger issues. more than likely a vaccum leak.

[LKSi]

I'll look at it tomorrow again I already replaced the bolts and tried to turn it a bit. Thanks for the response

[RPM SYSTEMS]

the iacv is a servo . and the bushings go bad in the IACV due to coolent and other wet thing getting near the bushings. when you take off the iacv you will see the flap is all gunked up .

[LKSi]

the iacv is a servo . and the bushings go bad in the IACV due to coolent and other wet thing getting near the bushings. when you take off the iacv you will see the flap is all gunked up .

That's the thing, when I took it apart it seemed really clean. I cleaned it again with carb cleaner just in case and put it back together. I'll be on the lookout for vacuum leaks tomorrow.

[RPM SYSTEMS]

did this just start or when you this is the first time you started your engine?

[LKSi]

did this just start or when you this is the first time you started your engine?

It's been like this since the first time I started it, but the first time I knew I had some vacuum leaks. I thought I had fixed all of them now.

[RPM SYSTEMS]

does the car think it is drive 3 ? if not there might be one of your problems. do you have B14 and D14 wired together ?

[LKSi]

does the car think it is drive 3 ? if not there might be one of your problems. do you have B14 and D14 wired together ?

Yes those two are wired together. It runs and drives ok, the idle seems to be the biggest issue.

[RPM SYSTEMS]

then try this .

disconnect the B14 and D14 wire.

connect the B14 to any ground while car is running.

what you are doing , is making the car think that the car is in park and the duty cycle should increase and the car should smooth out . this will tell you if the car's iacv is working .

tell me tomorrow what happens.

[LKSi]

then try this .

disconnect the B14 and D14 wire.

connect the B14 to any ground while car is running.

what you are doing , is making the car think that the car is in park and the duty cycle should increase and the car should smooth out . this will tell you if the car's iacv is working .

tell me tomorrow what happens.

Thank you very much, I will try it.

[00crv6?]

has anyone considered the power steering high pressure switch wiring, as that also can have a surging effect on the idle if the wires are either frayed or grounded. just something we see at the dealer a lot. this can even set an iac DTC if it is bad enough. early on as a tech i had found myself doing a p.s. switch wiring repair for free after selling an iac valve with no results and a DTC still present.

[Purple94Coupe]

Check to see if theres air in the system. let the car idle with the cap off and see if it stops