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Base Idle Speed & Idle Mixture

NOTE: Base idle speed is set at factory. It should not require further adjustment unless plenum chamber is changed. The adjustment screw is sealed with a plug to prevent unauthorized alteration. Check ignition timing before attempting following procedure, since this will affect idle speed. See IGNITION TIMING  .
IDLE SPEED & CO LEVEL

Application Idle RPM CO Level
Base Idle Speed 500-550 0.5-1.0% Max
A/T In Neutral 665-735 0.5-1.0% Max
A/T In Gear, A/C On 622-678 0.5-1.0% Max
A/T In Gear, A/C Off 572-628 0.5-1.0% Max
M/T 672-728 0.5-1.0% Max
M/T, A/C On 722-778 0.5-1.0% Max