ECM Non-Monitored Systems

The ECM does not monitor the following circuits, systems or conditions that could have malfunctions that result in driveability problems. A DTC will not be displayed for these conditions.

Cylinder Compression:  The ECM cannot detect uneven, low, or high engine cylinder compression.

Exhaust System:  The ECM cannot detect a plugged, restricted or leaking exhaust system.

Vacuum Assist:  Leaks or restrictions in the vacuum circuits of the Exhaust Gas Recirculation System (EGR) are not monitored by the ECM.

ECM System Ground:  The ECM cannot determine a poor system ground. However, a DTC may be generated as a result of this condition.

ECM/PCM Connector Engagement:  The ECM cannot determine spread or damaged connector pins. However, a DTC may be generated as a result of this condition.