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Home >> Honda >> 1987 >> Prelude L4-1955cc 2000 >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Idle Up Control Valve >> Adjustments
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Idle Up Control Valve: Adjustments


1987 Prelude
1. Start engine and warm to normal operating temperature.
2. Connect tachometer to engine.
3. Disconnect upper vacuum hose of idle control solenoid valve from intake manifold.
4. Cap end of hose and intake manifold.
5. Check idle speed with headlights and all accessories off. If idle speed is not 700---800 RPM, adjust idle speed by turning adjusting screw on top of throttle body.
6. Check idle with heater fan switch at HI and A/C on. If idle speed is not 700---800 RPM, adjust by turning adjusting bolt on A/C idle boost valve.
7. Connect idle control solenoid valve vacuum hose.
8. After adjusting idle speed on models with automatic transmission, ensure it remains within specified limit when shifted into D3 or D4.



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