Cold Engine Test
- With coolant temperature below 149°F (65°C), start engine and run at idle speed. Disconnect No. 12 vacuum hose from intake manifold and check for vacuum. See Fig 1 . If vacuum is not present, check vacuum port. If vacuum is present, check vacuum hose for proper connection, blockage and cracks. If vacuum line is okay, reconnect hose.
- Disconnect 6-wire connector near control box at center of firewall. See Fig 2 . Using a voltmeter, connect positive probe to Black/Yellow terminal of connector, and negative probe to Red/White terminal of connector. If voltage is present, replace solenoid valve and retest.
- If voltage is not present, move negative probe of voltmeter to good body ground and check for voltage. If voltage is not present, repair open in Black/Yellow wire between solenoid valve and 10-amp fuse in fuse block (fuse No. 4).
- If voltage is present, check for open in Red/White wire between solenoid valve and electronic control unit. If wire is okay, check control unit. Remove test equipment and reconnect all electrical connectors.