Possible Causes
| POSSIBLE CAUSES |
|---|
| EXHAUST LEAK |
| OXYGEN SENSOR WIRING OR CONNECTORS |
| O2 SENSOR SIGNAL CIRCUIT |
| O2 SENSOR RETURN CIRCUIT |
| 1/2 OXYGEN SENSOR |
| POWERTRAIN CONTROL MODULE (PCM) |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .