Another erratic idle question here...

[JG Luder]

okey dokey... I've done a search, but can't really find a direct answer. I do have a bored out TB.

My car is possessed. At random points in time, whether cold, or hot, A/C on, or off, it will jump in idle up and down anywhere from 500rpm-2000 rpm, usualy in 1000-1500 incriments. This is a common problem, I know.

Ex: Start the car, it idles fine, then sits for 30 seconds and starts revving from 500-1500 rpm... tap gas, it may or may not stop.

A lot of the time, if it's hot outside, and the A/C is on, then it will do it, and not be able to stop it unless the A/C is off, sometimes even that won't help, and even a few times it will be able to be stopped by tapping tha gas and NOT turning off the A/C.

Sometimes it will start and stop all on it's own.

I haven't done the "coolant bypass" thing.
I've checked extensively for vacuum leaks, and there are NONE. Here's the kicker, NO CODES. Not a damn one in a year relating to this.

I'm miffed. My question is, it's time to start replacing stuff, one at a time. Which would you suggest starting with? If you guys don't have any ideas, then I'll just tell Don to start replacing at will... I guess start cheap and work my way expensive.

?? Any ideas?

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"It seemed like a good idea at the time..."

Drive it like you stole it.
If it isn't broken, fix it till it is.

http://www.hondaprelude.com/setups/s...gen=4&orderby=

[blownintegra]

My friend had a 'Lude do the same thing to him. The dealer said it was all in his mind. I still believe it does it from time to time. Maybe it's a coolant temperature sensor on the blink, making your motor think it's cold and bumping up the idle?????

[JG Luder]

*Mumbles*
Goddamned Preludes...

Well, that's one more thing to check anyway. Thanks!

------------------
"It seemed like a good idea at the time..."

Drive it like you stole it.
If it isn't broken, fix it till it is.

http://www.hondaprelude.com/setups/s...gen=4&orderby=

[[MacGyver]]

Mine has done this several times over the past few years

#1 i have a vaccum leak from the evap purge canister causing it.

#2 My throttle cable was to tight and wasnt closing all the way and it would Idle funky

#3 i had an air bubble in the coolant line and it some how made it do it.

#4 Well im not sure why its doing it right now ill get back to you on that.

hehe

Matt

[JG Luder]

IT was doing it before the cams. now it's doing it after. I've sprayed everything with I think carb cleaner? Might have been starting fluid, it was a few months ago, and no effect in idle or hissing, or anything. It just ran off and dropped to the ground without a hint of promise to help me find what's wrong.
Oh well... it's just so damn erratic. It did it when I started it this morning, then stopped. Then didn't do it at all on the way to work until I stopped at a light, and it sat for a second or two, then started... then stopped after about 30 seconds. All on it's own. All of this when the A/C was on. ??? Damn possessed car... I need an exorcist, not a mechanic.

------------------
"It seemed like a good idea at the time..."

Drive it like you stole it.
If it isn't broken, fix it till it is.

http://www.hondaprelude.com/setups/s...gen=4&orderby=

[JG Luder]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>#4 Well im not sure why its doing it right now ill get back to you on that.<HR></BLOCKQUOTE>
LOL... hahahaha.

------------------
"It seemed like a good idea at the time..."

Drive it like you stole it.
If it isn't broken, fix it till it is.

http://www.hondaprelude.com/setups/s...gen=4&orderby=

[waveoff]

JG, I know you said that you checked extensively for vac leaks. Did you try spraying some starting fluid around? The other night my buddy and I were working on his civic trying to find a vac leak. We look at every damned connection and couldn't seem to find it. Long story short, it turned out to be a leaky intake manifold gasket. Try checking your gaskets and stuff. I see that you have crazy cams in your list of mods...perhaps the crazy idle is just one of those things one has to deal with. Hope ya figure it out.

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Fred G.
'97 Civic EX supercharged http://www.geocities.com/motorcity/track/4059
Beech 1900D driver...2,558 shp, 10,000+ ft./lbs. tq., top speed 331 mph