Catalytic Converter: Testing and Inspection

INSPECTION AND VERIFICATION
1. Verify the customer's concern or complaint.
2. Visually inspect the components of the catalyst and exhaust system.
3. Exercise the wiring and connectors for the solenoids and other components for obvious problems due to looseness, corrosion, or other damage.
4. Check the vacuum lines and connections for looseness, pinching, leakage, splitting, blockage, or other damage that may cause malfunction.
5. If a vacuum line or orifice (restrictor) blockage is suspected as the obvious cause of malfunction, correct the cause before proceeding to the next step.
6. Check engine oil for fuel dilution.
7. If all checks are OK, proceed to Exhaust Leakage or Noise check.

EXHAUST LEAKAGE OR NOISE
At idle or during normal driving conditions, a buzz or rattle may be detected which can be traced to the exhaust system. This may be due to a loose or damaged heat shield on the exhaust pipes, three way catalytic converter warm-up three way catalytic converter, or on the muffler. Loose or damaged heat shields should be repaired or replaced as soon as possible to maintain vehicle safety.

Damaged or deteriorated exhaust converter outlet gaskets, pipes or mufflers can also be the cause of a noisy exhaust system. These components should be repaired or replaced when they are found to be defective to maintain vehicle safety. If no obvious component can be identified, proceed to: Powertrain Management/diagnostic Routines.