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Home >> Isuzu >> 1982 >> I-Mark L4-1.8L 4FBI DSL >> Repair and Diagnosis >> Powertrain Management >> Tune-up and Engine Performance Checks >> Idle Speed >> Adjustments >> Fast Idle Adjust
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Fast Idle Adjust


1. Apply parking brake and block drive wheels.
2. Start engine and allow to reach normal operating temperature, then connect suitable tachometer.
3. Disconnect hoses from vacuum switch valve, then using a suitable pipe connect hoses together.


Fig. 10 Adjusting fast idle speed.:





4. Adjust fast idle speed to specifications by loosening locknut A and turning adjusting nut or screw B, Fig. 10 until specified speed is obtained.
5. Tighten locknut, reconnect vacuum switch valve and disconnect tachometer from engine.



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