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Cold Start Valve

  1. With ignition off, disconnect coolant temperature sensor. Unplug Green cable on ignition control module. Crank engine and check voltage at plug of cold start valve. Voltage should be 10 volts for about 9 seconds. If okay, test is complete. If not okay, go to step 2).
  2. Check wire from cold start valve to fuel pump relay (terminal No. 4) and ground wire to engine for continuity. Resistance should be zero ohms. If not, repair open circuit. Go to step 3). If okay, test is complete. See Fig 1 .
    Fig 1: Measuring Cold Start Valve Connector
    G48219
  3. With coolant temperature sensor disconnected, check voltage between fuel pump relay connector, terminal No. 12 and engine ground (-). Check terminal No. 2 (TF circuit) and engine ground (-). Crank engine (do not start). Voltage at terminal No. 12 should be 10 volts. Voltage at terminal No. 2 should be 3.5-5.0 volts. If not to specification, repair wiring circuits. If okay, replace fuel pump relay. End of test.