Diagnosis And Testing

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EXHAUST SYSTEM DIAGNOSIS CHART

CONDITION	POSSIBLE CAUSE	CORRECTION
EXCESSIVE EXHAUST NOISE	1. Leaks at pipe joints.	1. Tighten flanges to specified torque at leaking joints. Refer to TECHNICAL SPECIFICATIONS .
	2. Burned, rusted-out, or blown out muffler.	2. Replace muffler/tailpipe assembly. Refer to MUFFLER, EXHAUST, REMOVAL . Check exhaust system.
	3. Burned or rusted-out exhaust pipe.	Replace exhaust pipe.
	4. Exhaust pipe leaking at manifold flange.	4. Tighten connection attaching nuts. Refer to TECHNICAL SPECIFICATIONS .
	5. Exhaust manifold cracked or broken.	5. Replace exhaust manifold. Refer to REMOVAL, 5.7L .
	6. Leak between exhaust manifold and cylinder head.	6. Tighten exhaust manifold to cylinder head stud nuts or bolts. Refer to TORQUE SPECIFICATIONS .
	7. Restriction in muffler or tailpipe.	7. Remove restriction, if possible. Replace muffler or tailpipe, as necessary.
	8. Exhaust system contacting body or chassis.	8. Re-align exhaust system to clear surrounding components.
	9. Electronic active exhaust valve stuck open. NOTE: DTC should set	9. Requires the use of a diagnostic scan tool. Refer to diagnostic service information.
LEAKING EXHAUST GASES	1. Leaks at pipe joints.	1. Tighten flanges. Refer to TECHNICAL SPECIFICATIONS .
LACK OF POWER	1. Electronic active exhaust valve stuck closed. NOTE: DTC should set	9. Requires the use of a diagnostic scan tool. Refer to diagnostic service information.
	2. Restriction in muffler or tailpipe.	2. Remove restriction, if possible. Replace muffler or tailpipe, as necessary.
	3. Restriction in catalytic converter.	3. Remove restriction, if possible. Replace catalytic converter.
EXHAUST RATTLES ON ACCELERATION AND DE-ACCELERATION IN 1500-2400 RPM ZONE WHEN SPORT MODE IS OFF	1. Electronic active exhaust valve pin rattles.	1. Replace muffler/tailpipe (cold end exhaust) assembly.