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Old 07-04-2005, 01:06 AM   #1
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Default High Rpm'*

Well i went out and started the car today and the first time i started it, the idle was at around 1500rpm'*...normally sits round 1000rpms.

So i went driving around and it idled extremely high the whole time...kinda like my throttle was stuck open or something...i dunno. But anyway, i got home, stopped the car and turned it back on after a couple of seconds and it did its normal drop to 1000rpms.

Just wondering what the problem would be and i wanna stop it before it gets worse. Thanks for the help.

Dave
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Old 07-04-2005, 10:29 AM   #2
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Well, the ECU controls the idle, via the IAC. The IAC controls how much air passes through, while the TB is closed. When you restarted the car, did the idle drop from 1500 down to 1000? Or did the car start, and immediately land at 1000?


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Old 07-04-2005, 12:18 PM   #3
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Normally when the car starts, it will shoot up to 1500rpms and then make a fast drop to 1000rpms.

Well this time it shot to 1500rpms on start up and stayed there. So i drove around, then i stopped the car and it landed right at 1000rpms when i restarted.

The gradual decline of rpms is usually only happens when i havent driven the car for a couple of hours...like in the morning.
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Old 07-04-2005, 12:39 PM   #4
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Hmm.. sounds like there may have been an air leak or something. If it never comes back, don't worry about it. If it does, then I think a good IAC and TB cleaning will be in order. Actually, maybe you should do that anyways? It doesn't hurt.


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Old 07-04-2005, 01:17 PM   #5
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ok thanks for the help.

dave
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Old 07-04-2005, 01:23 PM   #6
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I second the "dirty/stuck" IAC theory, it makes perfect sense & theres nothing to lose by cleaning it.
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Old 08-03-2005, 07:17 PM   #7
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Um.... I dunno why no one mentioned this. Thats a fast idle. When the car is cold, so it can reach its normal operating temp faster, and run more efficiently. The reason the idle was fine after you restarted it was because the engine was still hot. Its supposed to do that, so its actually a problem if it doesn't.
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Old 08-04-2005, 05:34 AM   #8
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Quote:
Originally Posted by sleepy231
Um.... I dunno why no one mentioned this. Thats a fast idle. When the car is cold, so it can reach its normal operating temp faster, and run more efficiently. The reason the idle was fine after you restarted it was because the engine was still hot. Its supposed to do that, so its actually a problem if it doesn't.
It sounds like his idle continued to be high though, while driving it. That is abnormal.

I agree with the above: If it never happens again, swell. If it comes back, try cleaning stuff first...
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Old 08-04-2005, 10:28 AM   #9
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I do not believe our cars are supposed to do that, though. I could be wrong, but I know mine has never done that. And don't say i've just never seen it. The car has been in the family since 91, I've seen it all.
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Old 08-04-2005, 04:06 PM   #10
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Mine only does the high-idle-until-warm thing when it'* near freezing or below. It does it just a bit in the summer, but right away after starting it drops off and goes down to just slightly above the usual, operating temperature, idle speed.
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