Test Description
The numbers below refer to the step numbers on the diagnostic table.
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 an exhaust back pressure gauge.
Removing the heated oxygen (HO2S) sensor may set a diagnostic trouble code (DTC). When finishing this diagnostic table, be sure to clear all codes.
4
This step will isolate the catalytic converter from the remainder of the exhaust system.
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you verify the customers complaint? | Go to Step 2 | |
| 2 | Did you review the exhaust symptoms diagnostic information and perform the necessary inspections? | Go to Step 3 | Go to SYMPTOMS - ENGINE EXHAUST |
| 3 | WARNING: While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system. Remove the pre-catalyst HO2S. Refer to one of the following: HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 1 for the 2.0L engine. HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 1 for V6. Install the an exhaust back pressure gauge in place of the HO2S. Start and run the vehicle. Increase the engine speed to 2 500 RPM. Monitor the engine speed. Diesel only: Perform a manual regeneration of the particle filter Observe the exhaust system back pressure reading on the gauge. Diesel: Must not exceed 4 KPa Petrol: Must not exceed 0, 5 KPa Does the reading exceed the specified value? | Go to Step 4 | Go to Step 7 |
| 4 | Turn the engine OFF and place the ignition in the lock position. Remove an exhaust back pressure gauge. Install the pre-catalyst HO2S. Refer to one of the following: HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 1 for the 2.0L engine. HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 1 for V6. Remove the post-catalyst HO2S. Refer to one of the following: HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 2 for the 2.0L engine. HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 2 for V6. Install the an exhaust back pressure gauge in place of the post HO2S. Start the engine. Increase the engine speed to 2 500 RPM. Monitor the engine speed. Diesel only: Perform a manual regeneration of the particle filter Observe the exhaust system back pressure reading on the gauge. Diesel: Must not exceed 4 KPa Petrol: Must not exceed 0, 5 KPa Does the reading exceed the specified value? | Go to Step 5 | Go to Step 6 |
| 5 | Inspect the exhaust system for the following conditions: Damage in the exhaust pipe Debris in the exhaust pipe Muffler or resonator internal failure Muffler or resonator internal failure Two-layer exhaust pipe separation Did you find and correct the condition? | Go to Step 7 | |
| 6 | Replace the catalytic converter. Refer to CATALYTIC CONVERTER REPLACEMENT (LAU/A28NER) , CATALYTIC CONVERTER REPLACEMENT (LHU/A20NFT) or CATALYTIC CONVERTER REPLACEMENT (LHU/A20NFT - AWD) . Did you find and correct the condition? | Go to Step 7 | |
| 7 | Remove an exhaust back pressure gauge. Install the post-catalyst HO2S. Refer to one of the following: HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 2 for the 2.0L engine. HEATED OXYGEN SENSOR REPLACEMENT - SENSOR 2 for V6. Clear any codes. Road test the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
| WARNING |
|---|
| While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system. |