Catalytic Converter: Service and Repair
CATALYTIC CONVERTERREMOVAL
RIGHT HAND CATALYTIC CONVERTER
WARNING: The normal operating temperature of the exhaust system is very high. therefore, never work around or attempt to service any part of the exhaust system until it is cooled. special care should be taken when working near the catalytic converter. The temperature of the converter rises to a high level after a short period of engine operation time.
1. Disconnect negative battery cable.
2. Raise vehicle on hoist.
3. Disconnect downstream oxygen sensor (2) connectors.
4. Remove muffler and resonator.
5. 2.7L/3.5L Only - Remove nuts and cross-brace (2).
6. Remove catalytic converter to ball flange nuts (1).
7. Remove catalytic converter (3).
LEFT HAND CATALYTIC CONVERTER
1. Raise vehicle on hoist.
2. Hoist vehicle.
WARNING: The normal operating temperature of the exhaust system is very high. therefore, never work around or attempt to service any part of the exhaust system until it is cooled. special care should be taken when working near the catalytic converter. The temperature of the converter rises to a high level after a short period of engine operation time.
3. Disconnect downstream oxygen sensor electrical connectors.
4. Remove muffler and resonator assembly.
5. Remove ball flange nuts.
6. Remove catalytic converter ball flange nut.
7. Remove catalytic converter.
INSPECTION
WARNING: THE NORMAL OPERATING TEMPERATURE OF THE EXHAUST SYSTEM IS VERY HIGH. THEREFORE, NEVER ATTEMPT TO SERVICE ANY PART OF THE EXHAUST SYSTEM UNTIL IT IS COOLED. SPECIAL CARE SHOULD BE TAKEN WHEN WORKING NEAR THE CATALYTIC CONVERTER. THE TEMPERATURE OF THE CONVERTER RISES TO A HIGH LEVEL AFTER A SHORT PERIOD OF ENGINE OPERATION TIME.
Check catalytic converter for a flow restriction.
Visually inspect the catalytic converter element by using a borescope or equivalent. Remove oxygen sensor(s) and insert borescope. If borescope is not available, remove converter and inspect element using a flashlight. Inspect element for cracked or melted substrate.
NOTE: Before replacing a catalytic converter, determine the root cause of failure. Most catalytic converter failures are caused by air, fuel or ignition problems.
INSTALLATION
RIGHT HAND CATALYTIC CONVERTER
1. Install catalytic converter (3) onto exhaust manifold ball flange. Only finger tighten nuts at this time.
2. Install muffler and resonator assembly.
3. Install bolts and cross brace (3). Tighten bolts to 55 Nm (40 ft. lbs.).
4. Tighten manifold ball flange nut to 12 Nm (106 inch lbs.).
5. Check clearance between exhaust module and fuel tank. Clearance is 14 mm (0.55 inch) for V8 engine and 16 mm (0.62 inch) for V6 engine.
6. Check clearance at rear tunnel reinforcement. Clearance is 15 - 20 mm (0.59 - 0.78 inch).
7. Adjust clearance as necessary.
8. Tighten ball flange nuts to 34 Nm (25 ft. lbs.).
9. Connect oxygen sensor (2) connectors.
10. Lower vehicle.
11. Connect negative battery cable.
12. Start the engine and inspect for exhaust leaks. Repair exhaust leaks as necessary.
LEFT HAND CATALYTIC CONVERTER
1. Install catalytic converter (3) onto exhaust manifold ball flange. Only finger tighten nuts at this time.
2. Install muffler and resonator assembly.
3. Install bolts and cross brace. Tighten bolts to 55 Nm (40 ft. lbs.).
4. Tighten manifold ball flange nut to 12 Nm (106 inch lbs.).
5. Check clearance between exhaust module and fuel tank. Clearance is 14 mm (0.55 inch) for V8 engine and 16 mm (0.62 inch) for V6 engine.
6. Check clearance at rear tunnel reinforcement. Clearance is 15 - 20 mm (0.59 - 0.78 inch).
7. Adjust clearance as necessary.
8. Tighten ball flange nuts to 34 Nm (25 ft. lbs.).
9. Lower vehicle.
10. Connect negative battery cable.
11. Start the engine and inspect for exhaust leaks. Repair exhaust leaks as necessary