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Home >> Ford >> 1989 >> Ranger 4WD V6-177 2.9L >> Repair and Diagnosis >> Powertrain Management >> Emission Control Systems >> Adjustments >> Idle Speed
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Idle Speed

Idle Speed Setting:






1. Disconnect idle speed control-air bypass solenoid.
2. With transmission in Neutral or Park, run engine at 2500 rpm/30 seconds.
3. Place automatic transmission in Park, manual transmission in Neutral.
4. Check/adjust idle rpm:
Turn the throttle plate stop screw to 725 rpm
5. Shut engine off and repeat Steps 2, 3 and 4.
6. Shut engine off and disconnect battery for a minimum of 5 minutes.
7. Engine off reconnect idle speed control-air bypass solenoid, verify the throttle is not stuck in the bore and linkage not preventing throttle from closing.
8. Start engine and stabilize for 2 minutes then goose engine and let it return to idle, lightly depress and release the accelerator. Let engine idle, if problem exists, refer to COMPUTER ENGINE CONTROLS/DIAGNOSTIC ROUTINES for other possible causes.



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