GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Check for faulty exhaust system components.

Are any of the components faulty?

--

Go to Step 2

Go to Step 3

2

Replace the faulty components.

Is there still exhaust leakage and/or excessive noise?

--

Go to Step 3

System OK

3

Check for leakage at the exhaust component joints or coupling.

Is there leakage at the exhaust component joints or couplings?

--

Go to Step 4

Go to Step 5

4

Align the components. Replace the gasket and tighten the flange bolts to specifications. If necessary, weld the joint where leakage is present. Refer to Fastener Tightening Specifications .

Is there still exhaust leakage and/or excessive noise?

--

Go to Step 5

System OK

5

Inspect for loose connections or leaks at the exhaust manifold and the three way catalytic converter.

Are there any loose connections at the exhaust manifold or the catalytic converter?

--

Go to Step 6

Go to Step 7

6

Tighten all the fasteners to specifications. Refer to Fastener Tightening Specifications .

Is there still exhaust leakage and/or excessive noise?

--

Go to Step 7

System OK

7

Check for a faulty exhaust manifold or manifold gasket.

Is the exhaust manifold faulty?

--

Go to Step 8

Go to Step 9

8

Replace any faulty exhaust manifolds or manifold seals. Refer to the following:

    •  Exhaust Manifold Replacement in Engine Mechanical - 3.5L
    •  Exhaust Manifold Replacement in Engine Mechanical - 3.5L

Is there still exhaust leakage and/or excessive noise?

--

Go to Step 9

System OK

9

Check for any leakage at the crossover pipe connection.

Is there any leakage at the crossover pipe connection?

--

Go to Step 10

--

10

Tighten the nuts and bolts to specifications. Refer to Fastener Tightening Specifications .

Is there still exhaust leakage and/or excessive noise?

--

--

System OK