For 1990-2009 cars

#### Restricted Exhaust System Check

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to Step 2 | Go to Powertrain OBD System Check
2 |

1. Remove HO2S 1.
2. Install Exhaust Back pressure tester J 35314-A, BT-8515, BT-8603 in place of HO2S 1
3. Engine idling at normal operating temperature
4. Observe the exhaust system back pressure reading on the gage.

Does reading exceed the amount in the value column?

8.6 kPa (1.25 psi)

Go to Step 4

Go to Step 3

3 |

1. With Exhaust Back pressure tester J 35314-A, BT-8515, BT-8603 or equivalent in place of HO2S 1
2. Engine at normal operating temperature.
3. Increase engine speed to 2000 RPM and observe gage.
4. Observe the exhaust system back pressure reading on the gage.

Does reading exceed the amount in the value column?

20.7 kPa (3 psi)

Go to Step 4

No trouble found. If a driveabilty symptom exists Refer to Symptoms

4 |

1. Install the HO2S 1.
2. Remove the HO2S 2
3. Install Exhaust Back pressure tester J 35314-A, BT8515, BT8603 or equivalent in place of HO2S 2
4. Engine at normal operating temperature.
5. Increase engine speed to 2000 RPM and observe gage.
6. Observe the exhaust system back pressure reading on the gage.

Does reading exceed the amount in the value column?

20.7 kPa (3 psi)

Go to Step 5

Go to Step 6

5 | Repair restriction in the exhaust system after the Three Way Catalytic Converter. Possible faults include:

• | Collapsed pipe

• | Heat distress

• | Internal muffler failure

Is action complete?

--

Go to Step 7

--

6 | Replace the Three Way Catalytic Converter. Is action Complete? | -- | Go to Step 7 | --
7 |

1. Remove HO2S 1.
2. Install Exhaust Back pressure tester J 35314-A, BT-8515, BT-8603 or equivalent in place of HO2S 1
3. Engine idling at normal operating temperature
4. Observe the exhaust system back pressure reading on the gage.

Does reading exceed the specified value?

8.6 kPa (1.25 psi)

Go to Step 4

Go to Step 8

8 |

1. With exhaust back pressure tester J 35314-A, BT-8515, BT-8603 or equivalent in place of HO2S 1, increase engine speed to 2000 RPM.
2. Observe the exhaust system back pressure reading on the gage.

Does reading exceed the specified value?

20.7 kPa (3 psi)

Go to Step 5

Repair Complete