Oxygen (O2) Sensor
- Start and warm engine to operating temperature. Pull back seal at oxygen sensor connector. Using a DVOM with at least a 10-megohm input impedance, backprobe oxygen sensor connector.
- Increase engine speed to 2000 RPM and hold for about one minute while watching voltmeter. Reading should fluctuate between zero and one volt, without being constantly high or low. If voltage is not as specified, see CODE 13 in appropriate TESTS W/CODES article.