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

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

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Idle Speed

NOTE: Because it is ECU controlled, checking and adjusting idle speed is not usually necessary. When test connector (Green: 1-pin) is grounded, it disables ECU idle speed control. If rough idling due to low idle speed occurs when test connector is grounded, idle speed should be adjusted.


1. Check engine condition (spark plugs, leaks in hoses, etc.).
2. Turn all electrical loads OFF.
3. Warm up engine and run for three minutes at 2500 - 3000 rpm.

Fig. 21 Test Connector:






4. Connect tachometer to engine (white check connector on turbos)
5. Ground test connector (green: 1-pin) with a jumper wire.
6. Check that idle speed is within specification.

750 ± 25 rpm in neutral or park

Fig. 26 Idle Adjustment:






7. If not within specification, adjust by turning air adjusting screw.
8. After adjustment, disconnect jumper wire from test connector.