Testing and Inspection of Oxygen Sensor for Carburetor Equipped B Series Truck 2WD 22L (1990)
Oxygen Sensor: Testing and Inspection
Carburetor
Testing Oxygen Sensor
1. Warm up engine and run at idle.
2. Disconnect oxygen sensor wiring harness connector.
3. Connect voltmeter between oxygen sensor connector (oxygen sensor side) and ground.
4. Run engine at 4,000 rpm until voltmeter indicates approx. 0.7 volts.
Voltmeter Reading
5. Increase and decrease engine speed suddenly several times. When speed is increased, check that voltmeter reads between 0.5 and 1.0 volts. When
speed is decreased, check that voltmeter reads between 0 and 0.4 volts.
6. If not as specified, replace oxygen sensor. Connect oxygen sensor connector.
Self Diagnostic Checker Installed
7. Connect self diagnosis tester to check connector and negative battery terminal.
NOTE: Do not ground test connector (Green:1-pin) during this test.
