Diagnostic Aids
Caution: While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
The exhaust system has very low backpressure under normal conditions. If the exhaust system is restricted, a significant increase in exhaust pressure is noticed on the J 35314. Note: Removing the O2S sensor may set a DTC. When finishing this diagnostic table, be sure to clear all codes.
-
This step will isolate the catalytic converter from the remainder of the exhaust system.
-
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.
Step | Action | Values | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you verify the customer's complaint? | -- | Go to Step 2 | -- | ||||||||
2 | Did you review the exhaust symptoms diagnostic information and perform the necessary inspections? | -- | Go to Step 3 | |||||||||
3 | Is the system equipped with dual exhaust? | -- | Go to Diagnostic Aids | Go to Step 4 | ||||||||
Does the reading exceed the specified value? | 14 kPa (2 psi) | Go to Step 5 | Go to Step 7 | |||||||||
Inspect the exhaust system for the following conditions:
Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 6 | |||||||||
6 | Replace the catalytic converter. Refer to Catalytic Converter Replacement or Auxiliary Catalytic Converter Replacement . Is replacement complete? | -- | Go to Step 7 | -- | ||||||||
Did you correct the condition? | -- | System OK | Go to Step 2 |
