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Car keeps going with no throttle?

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Old Dec 20, 2003 | 07:50 PM
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Default Car keeps going with no throttle?

I have a missfire on #8, and now I've noticed that at idle if I tap the throttle my rpms go up to around 1500 and hold for 3-5 seconds and than drop back down. When I'm cruising, I can let go of the gas peddle and my car keeps driving. Any ideas on why this would be? Is this linked to missfire? This is really starting to suck > my baby is sick and the flu shot probably won't fix this either...
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Old Dec 20, 2003 | 09:35 PM
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1) Check your throttle linkage, ensure that it isn't set too tight / kinked etc... Make sure your throttle body is able to close all the way.

Disconnect your blower tubing from the inlet hat for these tests.

1) Check your LTerms with a scan tool. If they are pegged at 25% then start looking for a vacuum leak
2) Pull your IAT plug. If the engine takes off to ~3000 rpm then you defiantly have a vacuum leak.

Re-connect your blower:

1) Check your bypass valve. Ensure that it is bleeding off boost at low rpms. You can disconnect it from the inlet hat and you should actually be able to hear the boost blow off at any rpm. It makes a loud whoooshing noise.
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Old Dec 21, 2003 | 07:28 PM
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What is a IAT plug? Where is it located?
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Old Dec 21, 2003 | 09:32 PM
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The IAT is located in the air inlet tubing. On the ProCharger, it should be the little sensor in the Black Phlenum ontop the radiator.
Did you just start having this problem out of the blue, or have you performed mods, like a cam install and all of a sudden this happened?
Charlie.
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Old Dec 21, 2003 | 09:50 PM
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It's called the cruise control effect. You can do some searches for it, here is one small note on it: http://www.ls1camaro.net/viewtopic.p...=60&forum=15&0
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Old Dec 21, 2003 | 10:46 PM
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It just started out of the blue. First a missfire on #8 & #1. So I changed plugs and wires and this cruise control effect started. I have a friend from a dealership who's going to try to help me to find out missfire problem, but not sure if this was linked. My PCM was programmed by Ed W. and is it possible that the PCM would just stop working right? I'm hoping its related to missfire problem and when I fix that, all will be sloved. I shall find out tomorrow. Thanks for the help. I'll post my findings tomorrow.
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Old Dec 22, 2003 | 06:31 AM
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DOH!

I meant IAC plug.

IAT = Inlet Air Temperature. Does nothing for you to pull it.

IAC = Inlet Air Controller. Controls the amount of air let in at idle. Pulling it on a car with a vacuum leak will cause the car rpm to go high.

Sorry.
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Old Dec 22, 2003 | 08:57 PM
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Well today I found out that its not a bad injector. The search will continue. Going to try top end cleaner and pulling that IAC plug out and go from there.
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Old Dec 22, 2003 | 08:59 PM
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Oh yea, NoGo ~ when you say pull IAC plug out, do mean just unplug it? Or unscrew it? More info please....
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Old Dec 23, 2003 | 06:34 AM
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Start the car and let it idle for a couple seconds. Next, unplug the IAC (don't unscrew it or anything, just unplug the electrical connection from it).

Good Luck
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