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Home >> Honda >> 1991 >> Prelude L4-2056cc DOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Adjustments
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Computers and Control Systems: Adjustments

EACV And Connector:





1. Start engine and run to operating temperature (cooling fan comes on).
2. Connect a tachometer.
3. Disconnect the electrical connector from the EACV.

Idle Adjustment Screw:





4. Check idle speed with accessories off. Idle speed should be:

650 ±50 RPM (trans. in neutral or park)

Adjust the idle speed by turning the idle adjusting screw.
5. Turn off engine.
6. Reconnect the electrical connector to the EACV.
7. Remove the "CLOCK" fuse in the under-hood relay box for 10 seconds to reset the ECU.
8. Steps 8 and 9 are for USA vehicles only. Restart engine and run for one minute at idle speed with accessories off. Idle speed should be:

770 ±50 RPM (automatic transmission in drive)

9. Idle engine for one minute with heater fan (Hi) and air conditioner ON and recheck idle speed. Idle speed should be:

770 ±50 RPM (automatic transmission in drive)

10. If idle speed is out of specifications, see COMPUTERIZED ENGINE CONTROLS for testing of idle control system.
Disconnect the tachometer.

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