Restricted Exhaust
WARNING: This page is about a different car, the 2003 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
While engine is operating, the exhaust system will become extremely hot. To prevent burns, avoid contacting a hot exhaust system.
To check exhaust system for restrictions, see RESTRICTED EXHAUST under SYMPTOMS in TROUBLE SHOOTING - NO CODES - 4.0L AURORA article.