Test Description

The numbers below refer to the step numbers in the diagnostic procedure.

1. 3  - The exhaust system has very low back pressure under normal conditions. If the exhaust system is restricted, a significant increase in the exhaust pressure is noticed on the Gauge Bar Set (SA9127E), or the Backpressure Gauge (J 35314-A). Removing the Heated Oxygen Sensor (HO2S) sensor may set a DTC. When finishing this diagnostic table, ensure to clear all codes.
2. 4  - This step will isolate the catalytic converter from the remainder of the exhaust system.
3. 7  - Confirming that the condition has been fixed is essential. If the symptom still exists and the vehicle has a dual exhaust system, proceed to step  2 and repeat diagnostic procedure on the opposite exhaust pipe.