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Discussion Starter #1 (Edited)
Does anybody know how to test the Idle Air Control Valve attached to the throttle body? I'm beginning to suspect my no start condition is more related to this than vacuum leaks; while looking around I noticed coolant leaking out near the IAC. This would be a huge help, if it really did **** the bed than that may be why my car wont start. To further enforce my new theory, when I unplugged the IAC valve and tried to start the car, I got the same result as when it was plugged in. As always, any suggestions are welcome I am no expert!
 

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Does anybody know how to test the Idle Air Control Valve attached to the throttle body? I'm beginning to suspect my no start condition is more related to this than vacuum leaks; while looking around I noticed coolant leaking out near the IAC. This would be a huge help, if it really did **** the bed than that may be why my car wont start. To further enforce my new theory, when I unplugged the IAC valve and tried to start the car, I got the same result as when it was plugged in. As always, any suggestions are welcome I am no expert!

Take it out of the throttle body and connect a ground wire to it's housing. Then turn your key on and off. The pintle should move.
 

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Discussion Starter #5
So how can I test it without losing anything?

I ordered a new one anyway on the off chance it was the problem, if not I'll return it.

I'd still rather not need a new one if I don't need a new one.
 

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:doh: Fair enough.

So does anybody know if this particular component, if faulty, will result in a no start condition?

The engine starts with the pintle closed then the moment the engine starts the computer opens it up to the correct amount. But even if the pintle was wide open the engine should start. A no-start can only be caused by a lack of fuel or a lack of spark.
 

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What if it was stuck closed?

If it's stuck closed your engine will either idle real slow or won't idle at all. With your throttle closed the butterfly is just barely open to prevent sticking in it's bore. So the majority of air required to feed your engine at idle comes through the IAC pintle and it's bore. And with the throttle closed it would be very hard to start. The IAC valve is a computer controlled "stepper" motor that will run in either direction..........opening and closing the pintle as required to provide the engine the amount of air it needs during different situations such as A/C on or A/C off and and in DRIVE or not in DRIVE. And also provides more air for a cold-start fast idle. Your engine starts with the pintle fully withdrawn then it immediately screws in to limit the amount of air going into your engine. That's why you always start a fuel injected engine with a closed throttle as the pintle delivers the air needed.
 
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