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Idle Speed & Mixture

Idle mixture on fuel injected models is controlled by PCM and is not adjustable. Controlled idle speed and IAC count can be checked using scan tool. See CONTROLLED IDLE SPEED & IAC COUNT table. For controlled idle speed adjustment procedures, see ADJUSTMENTS - 7.4L article.

CONTROLLED IDLE SPEED & IAC COUNT

Application Idle RPM IAC Counts
7.4L 650 60