Non-Monitored Circuits

The PCM does not monitor all circuits, conditions and systems that could cause a malfunction or driveability problem. However, problems with these systems may cause PCM to store DTCs for other systems or components.

For example, a fuel pressure problem will not cause a DTC directly, but could cause a rich/lean condition or misfire. This could cause PCM to store an oxygen sensor DTC. The major non-monitored circuits are identified as follows.

• Cylinder Compression
• Engine Timing
• Excessive Oil Consumption
• Exhaust System
• Fuel Injectors
• Fuel Requirements
• PCM Grounds
• Secondary Ignition System
• Throttle Body Airflow
• Vacuum Assist