GM Service Manual Online
For 1990-2009 cars only

Exhaust Leakage - Not OBD II And/Or Excessive Noise

Step

Action

Value(s)

Yes

No

1

Inspect the components.

Are there any improperly installed or misaligned components?

--

Go to Step 2

Go to Step 3

2

  1. Align the components.
  2. Tighten the component connections to specifications. Refer to Exhaust System Clearances .

Is the exhaust system leaking and/or making excessive noise?

--

Go to Step 3

System OK

3

Inspect the connections at the exhaust manifold and the three way + oxidation catalytic converter.

Are there any loose connections at the exhaust manifold or the three way + oxidation catalytic converter?

--

Go to Step 4

Go to Step 5

4

Tighten all of the fastener connections to specifications. Refer to Exhaust System Clearances .

Is the exhaust system leaking and/or making excessive noise?

--

Go to Step 5

System OK

5

Inspect the exhaust manifold.

Is the exhaust manifold cracked or broken?

--

Go to Step 6

Go to Step 7

6

Replace the exhaust manifold. Refer to Exhaust Manifold Replacement .

Is the exhaust system leaking and/or making excessive noise?

--

Go to Step 7

System OK

7

Inspect the crossover exhaust pipe.

Is there leakage at the crossover exhaust pipe?

--

Go to Step 8

Go to Step 9

8

Tighten the nuts and the bolts to specifications. Refer to Exhaust System Clearances .

Is the exhaust system leaking and/or making excessive noise?

--

Go to Step 9

System OK

9

Inspect the seals.

Are the seals damaged or worn?

--

Go to Step 10

Go to Step 11

10

Replace the seals.

Is the exhaust system leaking or making excessive noise?

--

Go to Step 11

System OK

11

Inspect the intermediate exhaust pipe.

Is the intermediate exhaust pipe burned or rusted out?

--

Go to Step 12

Go to Step 13

12

Replace the intermediate exhaust pipe. Refer to Intermediate Pipe .

Is the exhaust system leaking or making excessive noise?

--

Go to Step 13

System OK

13

Inspect the muffler.

Is the muffler burned or rusted?

--

Go to Step 14

Go to Step 15

14

Replace the muffler/tailpipe assembly. Refer to Muffler .

Is the exhaust system leaking or making excessive noise?

--

Go to Step 15

System OK

15

Inspect the exhaust component joints and couplings.

Is there leakage at the exhaust component joints or couplings?

--

Go to Step 16

--

16

  1. Tighten the clamps to specifications. Refer to Exhaust System Clearances .
  2. Replace the clamps, if damaged.

Is the exhaust system leaking or making excessive noise?

--

--

System OK