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Wierd Idle Problems

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Old Aug 15, 2006 | 10:44 PM
  #1  
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Default Wierd Idle Problems

Ever since installing my new intake manifold, I've been having wierd idling issues. It doesn't seem to want to idle below 900 RPM's anymore, versus the 600 that it did before. Also, if I'm just in Neutral, give it a quick rev, it seems to stick at 1800 for about 3 seconds, then down to 1500 for another 3 secs, then back down to 900. The wierder thing is though, while I'm driving and I press the clutch pedal it revs up, in between shifts and while parking. All help again appreciated. Thanks
Old Aug 15, 2006 | 10:45 PM
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Default RE: Wierd Idle Problems

you may have a vaccum leak
Old Aug 16, 2006 | 12:54 AM
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Default RE: Wierd Idle Problems

A vacuum leak is what I had thought as well. I had a friend of mine check it all out while I was working today, he sprayed and couldn't find any leaks.
Also, I guess as an update, while I was driving it tonight if I let off the throttle it wants to stay at the same speed...not deccelerate as it should.
It's almost like its on permanent Cruise Control. And again very high idling when the clutch is depressed...around 1700 RPMS...it just jumps right up.
As for now I definitely think a vacuum leak is the problem. Any other possibilities anyone? Also would it still be ok to drive under this circumstance? Thanks again all
Old Aug 16, 2006 | 01:00 AM
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Default RE: Wierd Idle Problems

My truck was having Idle problems and it was the IAC. Maybe try checking the voltage on it?
Old Aug 16, 2006 | 01:34 AM
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Default RE: Wierd Idle Problems

This problem is common with my other car - Thunderbird Turbo Coupe. It required testing the throttle position sensor to see if there were any dead spots initially, then adjusting the idle (requires a DMM). I did that to the Tbird and the idle never hung again. I know its a different car/engine, but the problem sounds the exact same. Hope this helps.
Old Aug 16, 2006 | 01:38 AM
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Default RE: Wierd Idle Problems

Ever think it could just be your cable sticking?
Old Aug 16, 2006 | 01:45 AM
  #7  
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Default RE: Wierd Idle Problems

Ever think it could just be your cable sticking?
Possible, but I don't think likely, this problem occured immediately after the manifold swap... I dunno what to do...maybe I should just take the damn thing in to a shop (which I know we all hate to do)
Old Aug 16, 2006 | 01:59 AM
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Default RE: Wierd Idle Problems

I'd say vacum leak as well. Did you reset the computer? Give that a try.
Old Aug 16, 2006 | 02:04 AM
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Default RE: Wierd Idle Problems

I'd say vacum leak as well. Did you reset the computer? Give that a try.

Just unhook the negative battery cable for 15 mins??
Old Aug 16, 2006 | 02:07 AM
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ORIGINAL: Myfetang

I'd say vacum leak as well. Did you reset the computer? Give that a try.

Just unhook the negative battery cable for 15 mins??
There's a better way. Under the hood, there's a single wire black plastic quick connector by the starter solenoid. It's grounded to the metal by your wiper fluid resevoir. YOu can just disconnect that for a minute, and you'll keep all of you radio stations and stuff.



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