Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Emission Control Systems: Adjustments

Idle Speed Adjustment:






1. Warm engine to operating temperature. Connect tachometer.

Data Link Connector:






2. Turn engine and all accessories OFF. Ground PCM Self-Test Input (STI) pin at data link connector.
3. Start engine check idle speed. If not within specification, correct with idle speed adjustment screw.

IDLE SPEED: 700 - 800 rpm (with parking brake applied)

4. Turn engine OFF, remove STI ground, and let engine cool.
5. Start cold engine; idle speed should be higher than when warm.