Chugalug IACV!!!
07-01-2011, 02:09 AM
#11
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
That the idle dropped when you unplugged it indicates that it's working to some extent (it may still not be operating properly).
The TP sensor can cause high idle if defective--if the the PCM doesn't know the throttle is closed it will not control the idle). You'll need a voltmeter to test it¹, the voltage across the two wires (key on engine off, connected to the sensor, you'll need to backprobe it) should be 1.0V or less.
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¹ - You can get a workable and reasonably accurate multimeter at Harbor Freight for $5. They often have mounds of them for $3 at the stores...
The TP sensor can cause high idle if defective--if the the PCM doesn't know the throttle is closed it will not control the idle). You'll need a voltmeter to test it¹, the voltage across the two wires (key on engine off, connected to the sensor, you'll need to backprobe it) should be 1.0V or less.
-----------------------------------------
¹ - You can get a workable and reasonably accurate multimeter at Harbor Freight for $5. They often have mounds of them for $3 at the stores...
07-01-2011, 09:32 AM
#13
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
Has anyone messed with the throttle stop screw? This is often mistakenly thought to be a idle adjustment, but it is not. It's purpose is to hold the throttle open a small bit to let some air bleed through--not enough to idle the engine, but enough so that the IAC can control the idle up or down as needed.
If the TB is held too far open by the stop screw, when "closed", the IAC will not be able to properly control the idle...
07-01-2011, 06:16 PM
#14
2nd Gear Member
Join Date: May 2010
Location: Nebraska
Posts: 187
Btw you can pick up an IAC cheaper than 150....got mine through RockAuto.com for about $84 with new gasket as well shipped and arrived in like 3 days and it was a direct Motorcraft replacement just something to think about.
07-01-2011, 06:25 PM
#15
Gentleman's Relish
Join Date: Feb 2005
Location: AZ
Posts: 13,090
Rock auto has had pretty good prices on Motorcraft stuff for years now.
It wouldn't hurt to check the dealer though just for chits and giggles. I did that for an Escape hydraulic motor mount. Dealer wanted the same price as I had paid for an aftermarket one that didn't fit.
It wouldn't hurt to check the dealer though just for chits and giggles. I did that for an Escape hydraulic motor mount. Dealer wanted the same price as I had paid for an aftermarket one that didn't fit.
07-01-2011, 07:01 PM
#16
2nd Gear Member
Join Date: Apr 2008
Location: Va
Posts: 380
I just picked up one at Advance Auto for 60 bucks and some change, with the gasket.
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ShuggaShane05
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02-16-2011 10:01 PM
