The catalytic converter on a 2004 Pontiac Grand Prix is located under the vehicle. To remove it the bolts which connect it to the exhaust manifold must be removed. The bolts which connect it to the other piping will need removal as well. After all mounting hardware is off the converter will come off.
Needs a new catalytic converter.
You will need to replace it.
P0420 is a Catalytic Converter efficiency failer. More than likely you will need a new Catalytic Converter.
I have replaced hub bearings like 4 times on my 01 grand prix, anyone else have that problem and the catalytic converter 3 x
its before the cat usually on the driver side intake manifold
It might be the gravel shield for the catalytic converter. It can be removed.
had this promblem before check the catalytic converter it must be blocked,check the back pressure
First off it is illegal to run a vehicle that came from the factory with the converter removed. Secondly it will nor run good at all.
Check the catalytic converter.
its before the cat around the header area
02 Sensor? should be before the cat
i just bought one for a 1993 Pontiac grand Prix for 160.00 installed. This was for a universal converter. A new direct fit is 450+ dollars. Some cost over $1000