Wagoneer L6-258 4.2L VIN C 2-bbl (1982)
Oxygen Sensor: Testing and Inspection
1. Apply parking brake, start engine and increase speed to 2,000 RPM on front wheel drive models and 1,500 RPM on rear wheel drive models.
Make sure carburetor switch is not grounded.
2. Connect voltmeter to green solenoid output wire going to carburetor.
3. To perform full rich test, hold choke blades closed. During the next 10 seconds, voltage should decrease to 5 volts or less and remain there. If
engine does not respond, proceed to step 4.
4. To perform full lean test, disconnect PCV system at vacuum source. During the next 10 seconds, voltage should increase to at least 9 volts and
remain there until vacuum hose is connected.
5. If sensor fails tests in steps 3 and 4, replace. Connect all hoses and wires.
