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Makes 🢒 Chevrolet 🢒 2009 🢒 Aveo 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Restricted Exhaust

Special Tools

J 35314-A Exhaust Back Pressure Gage

Diagnostic Aids

Warning: 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.

Note: Removing the O2S sensor may set a DTC. When finishing this diagnostic table, be sure to clear all codes.

  1. 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-A .

  2. This step will isolate the catalytic converter from the remainder of the exhaust system.

    3.

  3. 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

Go to Symptoms - Engine Exhaust

3

Is the system equipped with dual exhaust?

--

Go to Diagnostic Aids

Go to Step 4

4

Note: Removing the oxygen sensor (O2S) may set a DTC. When finishing this diagnostic table, be sure to clear all codes.

  1. Remove the O2S that is in front of and closest to the catalytic converter.
  2. Install the J 35314-A in place of the O2S.
  3. Start the engine.
  4. Observe the exhaust system backpressure reading on the gage.

Does the reading exceed the specified value?

14 kPa (2 psi)

Go to Step 5

Go to Step 7

5

Inspect the exhaust system for the following conditions:

    • Damage to the exhaust pipe
    • Debris in the exhaust pipe
    • Muffler or resonator internal failure
    • Two-layer exhaust pipe separation

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.

Is replacement complete?

--

Go to Step 7

--

7

  1. Remove the J 35314-A and reinstall the O2S.
  2. Clear any codes.
  3. Road test the vehicle in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2