Test Description
NOTE:
Test numbers refer to numbers on diagnostic chart.
- Visually/physically checking components/systems which may cause a rich condition may determine cause of Code P0172.
- MAF sensor which causes PCM to read a higher then actual airflow can cause a rich condition, and Code P0172 to set.
- Silicone contamination of Heated Oxygen Sensor (HO2S) can cause a false rich indication that will be sensed by PCM. PCM will then reduce amount of fuel delivered, possibly causing severe driveability symptoms.