High Idle Than Bam Irratic Idle

[Accordturbo94]

Hey Ive had my h22 swapped in my car for a couple months now and out of the blue the other day, my car begain to idel high. About 1200-1300.. Than out of the blue it started the high idle to the irratic idle! I cant figure it out.. Ive checked for vac leaks. There was none.. I checked the TPS for voltage off my vafc.. .568ish closed and 4.?? at wide open. I tryed adjusting the idle on the throttle body.. its all the way closed and the revs still wont come down. Ive also checked the Idle Air Control Valve.. i disconnected it and the idle went down a bit.. but still the up and down revs. Im lost.. oh and Ive checked the timing.. thats great too. And I dont hear any leakes off the throttle body.. plus its a new gasket there..
I thought I would be as detailed as possible with this to help out. sorry its so lengthy. Its just hard to believe I got it to run great before.. and now its POO

 

[Accordturbo94]

?

 

[Accordturbo94]

yeah when i start my car in the morning or after work it revs high untill it warms up than it begins to go up and down!

 

[03jetta1.8t]

egr valve, probably sticks, and when it warms up the seal starts to flap up and down, most likely, engine light at all

 

[MXDesa]

Idle air motor. Right behind the intake manifold. Looks like a big solenoid. Change it with a new one. Trust me, i've encountered 3 honda motors with the same problem. Idle air motor every time.

 

[Accordturbo94]

thats on the f22! I have it on the front of the intake manifold! Im going to try to take it off and see if theres carbon in it! Is it possible that all of a sudden they will just go to poo! this thing ran awesome before!!! no codes just my vtec oil psi

 

[Accordturbo94]

Originally posted by 03jetta1.8t@Oct 27 2003, 08:59 PM
egr valve, probably sticks, and when it warms up the seal starts to flap up and down, most likely, engine light at all

the egr is not hooked up! if i remember right it gets blocked by my hondata intake manifold gasket! it has never been hooked up and when its not the car runs better!

 

[ahedau]

I talked to a family friend that's the service mgr for a local Honda dealer. He says its the IAC...not only 'cause of the irratic idle but because it changes once the car warms up. He said the shop fixes it by pulling the IAC and spraying carb cleaner in them to get rid of the carbon buildup. If the engine was sitting for any period of time before the swap that also could contribute to the problem of the IAC sticking causing you your headache.

Other than the IAC, remove the TPS and coat it in WD-40 and make sure there is no buildup there. Then put it all back together and everything should be okay.

 

[Accordturbo94]

Originally posted by ahedau@Oct 27 2003, 09:42 PM
I talked to a family friend that's the service mgr for a local Honda dealer. He says its the IAC...not only 'cause of the irratic idle but because it changes once the car warms up. He said the shop fixes it by pulling the IAC and spraying carb cleaner in them to get rid of the carbon buildup. If the engine was sitting for any period of time before the swap that also could contribute to the problem of the IAC sticking causing you your headache.

Other than the IAC, remove the TPS and coat it in WD-40 and make sure there is no buildup there. Then put it all back together and everything should be okay.

yeah i just took that beast off and blew it out with an air gun.. I didnt see this post in time to try wd40 but just blowing it off did not help! I took off the connector and than the idle dropped but it still just barely the idle went up and down.. So i just cant figure this thing out! I know my car is runnin real rich sut it coming out the exhaust and stains my damn floors but im thinkin its doing it because of the c.e.l. But thats another thing. I just want my car the way it ran 3 days ago! PERFECT

 

[Accordturbo94]

anyone else got a theory

 

[rudeludenotmeanthough]

vaccum leak.... the leading cause of all Honda idle headaches...

But really, check them.

 

[9k RPM EG6]

wrong gasket on the throttle body. they gave you the wrong gasket, it's blocking the warm start passages.

That or your EGR valve is going wacky (but do Preludes run EGR?). Voltage is normal at TPS, should be like 4.7 at WOT. check the gasket, I'm 99% sure you either installed it backwards or it broke or it's wrong.

Good luck bro!!!

-B

 

[9k RPM EG6]

you know, after reading more carefully, it MAY be the IAC. Normally though, the stepper motor begins sticking, so it'll grow worse progressively. If you disconnect it and it changes, it probably has nothing to do with the problem. Your stepper motor in the IAC only works so fast...so if you disconnect and it changes idle, but not a whole lot, prolly not the IAC. Change the Throttle Body Gasket. Otherwise get a "known good" IAC and see if it solves the problem.

I doubt your EGR is even connected. And yes, car should run MUCH better. Besides, EGR causes PISSED OFF IDLE, not irratic. Gasket or IAC.

-B

 

[MXDesa]

Originally posted by Accordturbo94@Oct 28 2003, 10:33 AM
anyone else got a theory

This is no theory about it. Whether the IAC is on the back or front, thats is the problem. Sorry about my mistake saying it was on the back. But change it with a good known one and it should solve the problem. Good Luck

 

[9k RPM EG6]

gotta love them "known good" parts....

-B

 

[Accordturbo94]

New gasket in the throttle body.. you know when those are bad, you can hear it a mile away!!! when i disconnect my IAC the idle comes down from the 1300-2500 bounce to like 12-1300. and yes it still bounces just a bit. The vaccum lines are great ive checked them many times and have put soap on them to check for bubbles... nadda! like i said one day my car just started to rev to about 1200.. didnt think much of it cause it wasnt to bad.. now as soon as i get in it to drive and its been sitting it revs to like 2900 till it warms up! vs the normal 1500 rpms it used to be like! than as soon as its warm it revs up and down from like 1300-2000 or so.. im not exacly sure how high it goes now! AHH this sucks

 

[Accordturbo94]

Originally posted by MXDesa+Oct 28 2003, 07:37 PM-->

Accordturbo94

@Oct 28 2003, 10:33 AM
anyone else got a theory

This is no theory about it. Whether the IAC is on the back or front, thats is the problem. Sorry about my mistake saying it was on the back. But change it with a good known one and it should solve the problem. Good Luck

as for a know good one.. i would be screwed! I have the only h22 in town.. lol!

 

[Jim Truett]

Originally posted by Accordturbo94@Oct 28 2003, 10:33 AM
anyone else got a theory

I have had a vacuum leak in the brake booster cause the same symptoms. Disconnect it, and plug the vacuum port that feeds it, and see if your problem goes away.

 

[Accordturbo94]

Originally posted by Jim Truett+Oct 28 2003, 11:53 PM-->

Accordturbo94

@Oct 28 2003, 10:33 AM
anyone else got a theory

I have had a vacuum leak in the brake booster cause the same symptoms. Disconnect it, and plug the vacuum port that feeds it, and see if your problem goes away.

hey that sounded pretty good at first but.. than i thought about it.. it wouldnt make it rev so high right away when i start it..

 

[Accordturbo94]

This BLOWS