Exhaust System - Rattle/Rumble On Cold Start Up

TECHNICAL

Bulletin No.: 09-06-05-002

Date: April 14, 2009

Subject:
Exhaust Rattle/Rumble on Cold Start Up (Perform Repair as Outlined)

Models:
2008-2009 Pontiac G8 (Including GT and GTX)

Condition

Some customers may comment on a rattle/rumble on cold start up for approximately 15-20 seconds. This rattle only occurs during a start from cold with fast engine idle. It can be aggravated by selecting drive during this period. Once idle returns to normal, the rattle will stop.

Cause





This condition may be caused by misalignment of the intermediate exhaust pipe to catalytic converter creating a contact point at the flanged joint.

Correction





Verify the customer concern. If as described above, disassemble the intermediate pipe to catalytic converter flange joint on both sides and reassemble with the specified torque sequence shown in picture above.

Tighten
Tighten the retaining nuts to 45Nm (30 lb ft).

Warranty Information





For vehicles repaired under warranty, use the table above.





Disclaimer