Engine Exhaust System: Overview Chevrolet Silverado 2500

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 4) - 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 the J 35314-A . Removing the AIR check valve or HO2S sensor may set a DTC. When finishing this diagnostic table, be sure to clear all codes.
2. 5) - This step will isolate the catalytic converter from the remainder of the exhaust system.
3. 8) - 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.

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

1. Raise and suitably support the vehicle.
2. Remove the exhaust manifold pipe nuts.
3. Lower the vehicle.
4. Remove the spark plug wire clip from the exhaust gas recirculation (EGR) valve inlet pipe tab.
5. Disconnect the spark plug wires from the spark plugs.
6. Remove the spark plug wire retainer bolts.
7. Position the wire harness on top of the engine.
8. Remove the spark plugs.
9. Remove the EGR valve inlet pipe from the intake and exhaust manifolds.
10. Disconnect the engine coolant temperature (ECT) sensor electrical connector.
11. Remove the exhaust manifold and spark plug wire shields bolts/stud.
12. Remove the exhaust manifold and plug wire shields.
13. Remove and discard the exhaust manifold gaskets.
14. Remove the exhaust manifold heat shield bolts and shield, if required.
15. Clean all gasket mating surfaces.

Exhaust System Description

Important: Use of non-OEM parts may cause driveability concerns.

The exhaust system carries exhaust gases, treated by the catalytic converter, through a resonator, if applicable and into the exhaust muffler where exhaust noise is lessened.

In order to secure the exhaust pipe to the exhaust manifold, a flange and seal-joint coupling is utilized. The exhaust system may utilize a slip-joint coupling design with a clamp and a U-bolt or a flange connection with a gasket.

Exhaust hangers and rubber insulators help to support the weight of the exhaust pipe along with insulating any exhaust system vibration, rattle, or noise.

Exhaust hangers also space the exhaust system away from the underbody of the vehicle and allows the exhaust system to expand as the exhaust system warms up.

Exhaust heat shields are used to protect the body and other components from damage due to the heat from the exhaust system.

The exhaust system may be comprised of the following components

1. Exhaust manifold
2. Exhaust pipes
3. Catalytic converters
4. Exhaust muffler
5. Exhaust resonator, if equipped
6. Exhaust tail pipe, if equipped
7. Exhaust hangers
8. Exhaust heat shields