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Idle Speed & Mixture (Gasoline): Notes

NOTE: DO NOT  attempt to adjust idle mixture and idle speed. Both are controlled by Electronic Control Module (ECM). Incorrect idle speeds are normally caused by dirty throttle plate or vacuum leaks. Ensure all vacuum components are functioning properly.
NOTE: Controlled idle speed and IAC count can be checked using scan tester. See CONTROLLED IDLE SPEED & IAC COUNT  table. Minimum idle speed adjustment can only be performed on the 7.4L engines. See MINIMUM IDLE SPEED ADJUSTMENT (7.4L).