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Problems with dying at idle and when letting off clutch.

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Old 12-07-2008, 05:32 AM
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99StangGTTN
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Default Problems with dying at idle and when letting off clutch.

When I let off my clutch or stop at lights my car usually nosedives in RPM's then shoots back up and then usually dies. I have replaced the TPS and Idle Air Control Valve. It just seems like the car doesn't know where it should be for idle. The strangest part is that this problem only happens about 60% of the time. The rest of the time when I let off the clutch the RPM's hang like they should and the car doesn't die. Any ideas?
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Old 12-07-2008, 01:55 PM
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jrherald420
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air idle control valve????
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Old 12-07-2008, 02:26 PM
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ZW99GT
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Originally Posted by jrherald420
air idle control valve????
Read the OP. He says he already replaced that.
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Old 12-07-2008, 02:40 PM
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03sixbanger
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my 97 was doing the same thing....now it just wont idle at all
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Old 12-07-2008, 02:42 PM
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mustang_pa
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start checking some hoses
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Old 12-07-2008, 02:47 PM
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jrherald420
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Originally Posted by ZW99GT
Read the OP. He says he already replaced that.
sorry i must have skipped over that.
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Old 12-08-2008, 05:36 AM
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99StangGTTN
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I have hooked it up to a smoke machine to check for vacuum leaks and none were found...... any other ideas?
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Old 12-08-2008, 11:11 AM
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mustang_pa
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do u have a hand held tuner? u can check for codes. U might have one. Did u recently do anything to the car? Besides replacing the tps and aic. Do u have a boost gauge? What does that read at idle? Do you any other sensors, like a air temp sensor that is hooked up for the turbo system that is connected via maf wires.
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Old 12-08-2008, 04:34 PM
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Dan04COBRA
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With all your mods, it sounds like there is a problem with your tune. It may have already been tuned and ran fine for a long while, but it's not unusual for a little quirk like this to show up sometime down the road, especially when the weather changes.
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Old 12-08-2008, 08:10 PM
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.boB
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On a lot of cars, this is a common symptom of battery failure. Have the battery load tested at your local Autozone (or whatever).
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