How to test the idle auxilary air valve? (2.6)

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How to test the idle auxilary air valve? (2.6)

Postby TroopDawg » Sat May 01, 2021 11:54 pm

Aka... “idle air control valve” or “auto choke”

I tried the PB blaster trick, not much help for me. My valve seems to be in the “stuck open” position... the vehicle reaches temp but the idle stays high. The idle snooths out to 900/1000 rpm if i clamp the IAC hose with vice grips...

If i set my timing to 12 degrees, the idle surges up and down.

If i set my timing to 0, the idle is smooth, but sits around 1500 rpm until i clamp off the IAC.

How do i know if its the IAC, thermal temp sensor or the computer itself?
Last edited by TroopDawg on Sun May 02, 2021 2:39 pm, edited 3 times in total.
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Re: 2.6 idle air control valve

Postby TroopDawg » Sun May 02, 2021 1:26 am

Its not the ecu, i got a code 12 3 times in a row. So the ecu is operating well. Wouldnt it recieve a code for a bad IAC or would it not if it is the temp sender(temp to ecu, not gauge)
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Re: 2.6 idle air control valve

Postby TroopDawg » Sun May 02, 2021 2:31 pm

How do i test the auxilary idle valve?

How does it communicate with the ECU? Is it powered by the ECU or is a signal sent to the ECU by the valve itself as it closes? Ibe read about a heat element within the valve itself? But ive also read that they rely on ambient engine heat to trigger.

How does this thing exactly operate?

I know its supposed to be open while cold and slowly closes while the engine gets hot.

If i clamp it while at operating temp... engine idles perfect.
When i remive it from the engine both hot or cold... its half open...

The valve plate inside of it feels spring and smooth...

Does the termal temp sensor (ecu sensor) comunicate that info to the AAV?

So confusing
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Re: How to test the idle auxilary air valve? (2.6)

Postby TroopDawg » Sun May 02, 2021 2:52 pm

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