AC and engine slow down

125,000 MILES • 6 CYL • 2WD • AUTOMATIC
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FAKLUN1
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When I turn on the AC the engine rpm's drops. At idle the drop can be as much as 400 rpm's. Any idea whats happening?
Nov 1, 2017 at 6:51 AM
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WRENCHTECH
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It is very normal for the AC to add additional load on the engine, but the IAC normally compensates for it. You should try first cleaning the inside of the throttle body and backside of the throttle plate, then remove the IAC and clean and lube the slide valve inside. That should stabilize the idle.
Nov 1, 2017 at 8:52 AM
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FAKLUN1
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What is IAC?
Nov 1, 2017 at 9:05 AM
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WRENCHTECH
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Idle Air Control

This picture may be from a different model, but it is basically the same.
Nov 1, 2017 at 9:10 AM
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FAKLUN1
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Where on the engine do you normally find it?
Nov 1, 2017 at 9:16 AM
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WRENCHTECH
  • ✓Experienced Mechanic
  • 20,760 POSTS
It will be in the manifold, near the throttle plate.
Nov 1, 2017 at 9:24 AM
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