Oxygen Sensor Test
- With engine at operating temperature but stopped, disconnect oxygen sensor connector. Start engine and run on high step of fast idle cam for 1 minute.
- Connect voltmeter between ground and sensor, then depress carburetor control vacuum regulator (CVR) rod for 10 seconds. Voltage should be more than 0.5 volts.
- Run engine at fast idle for 1 minute with PCV valve disconnected. Measure oxygen sensor voltage. Voltage should be less than 0.5 volts.
- If oxygen sensor does not function as described, retest. If voltage readings are still incorrect, replace sensor. Tighten sensor to 27-33 ft. lbs.