Exhaust System Diagnostic Chart

Fig 1: Exhaust System Diagnostic Chart

Courtesy of GENERAL MOTORS CORP.

NOTE: The muffler should move in the isolator block a minimum of 1.60 mm (1/16 in.) vertically and 3 mm (1/18 in.) horizontally to prevent vibrations from being transmitted into the vehicle's body.

NOTE: When a catalytic converter's catalyst fails, pieces of the converter can become lodged in the muffler causing poor acceleration/hesitation. A plugged catalytic converter can also cause the engine not to start when exhaust flow is completely blocked.