when it gets dunked
IAC question
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Instructor
Joined: Oct 2003
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From: Coweta OK
IAC question
I took my throttle body off and cleaned it. I did not take the IAC off when I did this. Now when it starts it wants to idle pretty fast, as in 1300-1400 rpms, for 30 seconds or so. It also bounces from 6,000 to 7,000 after it warms up. Did I ruin the IAC by not taking it off the throttle body? Any chance I can salvage the IAC?
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From: Almost all Skyline Cruises Vettes at Waterside 1-5
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Originally Posted by VettBrat
I took my throttle body off and cleaned it. I did not take the IAC off when I did this. Now when it starts it wants to idle pretty fast, as in 1300-1400 rpms, for 30 seconds or so. It also bounces from 6,000 to 7,000 after it warms up. Did I ruin the IAC by not taking it off the throttle body? Any chance I can salvage the IAC?
Simply removing the Throttle body should not affect the IAC as long as you reconnected all the electrical connections and throttle/shift cables properly
Why did you remove the Throttle Body? Where you experiencing a problem?
Jack
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From: The Top of Utah
How did you "clean" the TB? If you immersed it in cleaning fluid, like carb cleaner, it is probably toast. That wasn't much of a cleaning job, if you didn't remove the IAC and clean it and the IAC passages. That is one of the main parts that most oftenNEEDS cleaning. If it was immersed, let it dry out, keeping your fingers crossed the whole time. Once it is dry, or if it didn't get a bath, take the car out for a drive, warmed up, at a speed up to, or above 40 mph. That SHOULD reset it, if it is resettable. What did you do with the TPS?
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Thread Starter
Instructor
Joined: Oct 2003
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From: Coweta OK
Originally Posted by CFI-EFI
How did you "clean" the TB? If you immersed it in cleaning fluid, like carb cleaner, it is probably toast. That wasn't much of a cleaning job, if you didn't remove the IAC and clean it and the IAC passages. That is one of the main parts that most oftenNEEDS cleaning. If it was immersed, let it dry out, keeping your fingers crossed the whole time. Once it is dry, or if it didn't get a bath, take the car out for a drive, warmed up, at a speed up to, or above 40 mph. That SHOULD reset it, if it is resettable. What did you do with the TPS?
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From: SE NY
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It's likely that over time, as the TB carboned up, the ECM had to back out the IAC pintel more and more to bleed in enough air to maintain proper idle. By now the IAC passage is likely carboned up so that the ECM cannot extend the pintel deep enough to reduce air bleed and control idle properly.
So just pull the IAC motor and use TB cleaner to clean the pintel and the bore under the TB.
Then, if it's an L98, use the method on my site to set base idle and, if an '85-'89 L98, check the TPS values at base idle and WOT.
So just pull the IAC motor and use TB cleaner to clean the pintel and the bore under the TB.
Then, if it's an L98, use the method on my site to set base idle and, if an '85-'89 L98, check the TPS values at base idle and WOT.
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Originally Posted by VettBrat
I took my throttle body off and cleaned it. I did not take the IAC off when I did this. Now when it starts it wants to idle pretty fast, as in 1300-1400 rpms, for 30 seconds or so. It also bounces from 6,000 to 7,000 after it warms up. Did I ruin the IAC by not taking it off the throttle body? Any chance I can salvage the IAC?
I cleaned,adjusted and reset my idle twice in the last two years..I finally just gave up and bought a new IAC moter, cost less than $60.00 and car runs great!seeya
Jack
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From: Bergen County, NJ
Originally Posted by jackdaroofer
I cleaned,adjusted and reset my idle twice in the last two years..I finally just gave up and bought a new IAC moter, cost less than $60.00 and car runs great!
Just replace it. Here's what my old & new looked like.
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