Idle Control Solenoid Valve

When idle speed is reduced due to electrical or other loads on engine, this valve opens to by-pass additional air into intake manifold. This additional air will allow idle speed to increase to normal speed (700-800 RPM).

Operation depends upon changes in voltage at FR terminal of alternator for quicker response. After coolant temperature has reached 104°F (40°C), this valve lowers fast idle speed in steps during engine warm-up.

To prevent erratic running after engine first starts, valve is opened during cranking and immediately after starting to provide additional air into intake manifold.

1. Idle control solenoid valve is activated by commands from ECU. When solenoid valve opens, vacuum enters hose between air filter 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 1500-1700 RPM.
2. While solenoid valve is being activated, 9 volts or more should be available between Black terminal and Light Green terminal of valve leads.
3. Open control box lid and disconnect wiring harness from control box. Disconnect vacuum hose from between idle control solenoid valve and No. 10 vacuum hose. Connect vacuum gauge to hose and apply vacuum. It should hold vacuum.
4. Connect the positive battery terminal to the Black terminal of control box and negative battery terminal to Light Green terminl. Apply vacuum as in step 3). It SHOULD NOT hold vacuum.