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Idle Control Solenoid Valve

  1. Idle control solenoid valve is activated by commands from ECU. When solenoid valve opens, vacuum enters hose between air flow tube and solenoid valve. Idle speed increases for a short period after starting engine and whenever electrical loads are turned on.
    NOTE: Vacuum will disappear when engine RPM is raised over 1700 RPM.
  2. While solenoid valve is being activated, 9 volts or more should be available between Black terminal (A) and Light Green (B) of valve leads.
  3. Connect the positive battery terminal to the Black/Yellow terminal of control box and negative battery terminal to Green/Black terminal. Disconnect vacuum hose No. 28 from intake manifold. Apply vacuum to vacuum hose No. 26. It SHOULD NOT hold vacuum.
  4. On Civic CRX Si models, open control box lid and disconnect wiring harness from control box. Disconnect vacuum hose form between idle control solenoid valve and No. 10 vacuum hose. Connect vacuum gauge to hose and apply vacuum. It should hold vacuum.
  5. Connect battery positive terminal to control box connector Black terminal and negative terminal to Light Green terminal. Apply vacuum to hose. It SHOULD NOT hold vacuum.
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