Possible Causes
WARNING: This page is about a different car, the 2005 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
| Possible Causes |
|---|
| EXHAUST LEAK |
| ENGINE MECHANICAL |
| 2/2 O2 SENSOR |
| (K243) O2 2/2 SIGNAL CIRCUIT |
| (K399) O2 HEATER 2/2 CONTROL CIRCUIT |
| (K904) O2 RETURN DOWNSTREAM CIRCUIT |
| FUEL CONTAMINATION |
Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.