Grand Prix

Loss of Engine Power Due to Plugged Catalytic Converter on Pontiac Grand Prix

Problem Description and Possible Solution

The catalytic converter may become plugged resulting in loss of engine power. General Motors has extended the catalytic convertor warranty on some models to 10 years or 120,000 miles. Please contact your local GM dealer to see if your vehicle is included.

Problem Data
RepairPal Verified
Average mileage: 140,266 (65,000–230,000)
8 model years affected: 1994, 2001, 2002, 2004, more2005, 2006, 2007, 2008
48 people reported this problem
Viewing 1 - 19 of 19 comments
can't figure out the real problem . i changed coils,sparkplugs,air filter,and comb out converter car still will not stay running i need and answer
car not enough engine power,running rough,cutting out. giving more throttle makes it worse along with bad muffler. has been diagnosed with bad converter and fuel burning
Runs great when it is cold when it warms up and go to accelerate spits and spudders it throws 2 codes p0303, and p0420 I've done everything with# 3 cylinder plugs wires and tried another coil pack
The Catalytic converter may be faulty. I have lack of engine power and makes a whistling noise upon hard acceleration. The engine light is on due to the catalytic converter.
Loss of power causing the transmission to not shift out of first gear. Car is in the shop right now and I am currently being told it is a plugged Catalytic converter. Shop is trying to charge me $800 to fix it.