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  1. #1

    Default High idle rev w/ A/C on

    Just got an 89 Sub with a 454 and the TH400. The thing is in great condition, with 88K on it.

    I noticed the other day that when the a/c is on, the engine has an abnormally high rev. You don't notice it much above 20-30mph, but when you are braking and get back down to first gear it feels like your foot is still on the accelerator.

    Any ideas as to what is going on?

    Thanks in advance!

  2. #2
    murdog94's Avatar
    Join Date
    Feb 2008
    Cloquet, Minnesota, United States
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    Sounds like your IAC is opening to try and idle the motor up for the higher load with the AC on.. You might try pulling it and cleaning it off...


    1997 Chevy S-10 Blazer 4X4 with 330K miles and counting (Hunting rig).

    2009 Saturn Aura XE (wifes car)

    2011 F-150 Crew 4X4

    "Hold it to the floor till you see God.... Then Brake!!!!"

  3. #3


    Thanks! Now for a newbie question - where is it located at on the 454?

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