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Idle Speed & Mixture (Gasoline)

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 appropriate ON-VEHICLE ADJUSTMENTS article.

CONTROLLED IDLE SPEED & IAC COUNT

Application Idle RPM IAC Counts
1.6L 725-775 (1) 17-30
2.0L (2) (2)
2.2L (2) 5-60
3.4L (2) 10-40
4.3L, 4.8L, 5.3L & 6.0L (2) Varies
5.0L & 5.7L 650 Varies
7.4L 650 60
(1) Specification is duty cycle percentage.
(2) Information is not available from manufacturer.