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Fast Idle Control Solenoid Valve

NOTE: The fast idle control solenoid valve is open when coolant temperature is less than 5°F (-15°C). If coolant temperature is less than 104°F (40°C), solenoid is open only when atmospheric pressure is less than 26 in. Hg. Vacuum is supplied to vacuum hose between solenoid valve and air flow tube.
  1. When the valve is open, 9 volts or more should be available between Black/Yellow (A) and Blue/Black (B) terminals (Black (A) and Yellow (B) terminals on CRX Si) of control box No.1 wiring harness.
  2. Disconnect wiring harness from No. 1 control box. Disconnect vacuum hose No. 18 from air flow tube (vacuum hose between fast idle control solenoid valve and No. 10 hose on CRX Si). Apply vacuum to the hose. It should hold vacuum. See Fig 1 .
    Fig 1: Fast Idle Ctrl Solenoid Valve Test Civic CRX Si models shown
    G42704
  3. Connect battery positive terminal to Black terminal of No. 1 control box coupler, and battery negative terminal to Orange terminal (Yellow terminal on CRX Si). Disconnect vacuum hose No. 23 from intake manifold. Apply vacuum. It SHOULD NOT hold vacuum.