Malfunction Test 7

1. Increase engine speed to heat oxygen sensor. If reading changes slightly, complete ``System Test.''
2. Disconnect electrical connector at oxygen sensor and connect to ground.
3. If dwell reading increases to at least 68°, replace oxygen sensor.
4. If reading does not increase, check wire from oxygen sensor to electronic control module.
5. If wiring is satisfactory, replace electronic control module.
6. Perform ``System Test.''