Heat Shields: Operation
WARNING: This page is about a different car, the 2003 Dodge Intrepid, 2003 Chrysler Intrepid, 2003 Chrysler Concorde, and 2003 Chrysler 300M. However, it is still accessible from the selected car via links, so may be relevant.
Heat shields are needed to protect both the car and the environment from the high temperatures developed in the vicinity of the catalytic converters.
CAUTION:
Avoid application of rust prevention compounds or undercoating materials to exhaust system heat shields on cars if equipped. Light over spray near the edges is permitted. Application of coating will greatly reduce the efficiency of the heat shields resulting in excessive floor pan temperatures and objectionable fumes.