Description
An exhaust leak may show stains at the area of the leak. The leak may be felt by holding a hand close to the suspected areas or using a smoke pencil. The leak may make a popping or hissing noise.
An audible or physical noise due to a faulty component or damaged components causing a loose or misaligned exhaust system resulting in a rattle or vibration noise, buzz, groan or hum.
Test Description
The numbers below refer to the step numbers in the diagnostic procedures.
- 4 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 Exhaust Back Pressure Gauge (J 35314-A). Removing the AIR check valve or HO2S may set a DTC. When diagnosis is finished, ensure to clear all codes using the scan tool.
- 5 If high back pressure is not found at idle, increasing the engine speed may help find a restriction. Perform operational check before returning vehicle to customer.
- 6 This step will isolate the catalytic converter from the remainder of the exhaust system.
- 9 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.
See also:
• PID VALUE CHARTS