Depends on why it is noisy.
The catalytic converter is located underneath the vehicle in the first half of the exhaust, like a big bulge looking piece
On a 1998 Mercury Grand Marquis : Bank 1 is the passenger side of the engine Sensor 2 is AFTER the exhaust has passed through the catalytic converter
On a 1997 Mercury Grand Marquis : Bank 2 is the drivers side of the engine and ------------------------------------------------------------------------------------------ Sensor 1 would be close to the engine before the exhaust enters the catalytic converter Sensor 2 would be AFTER the exhaust has passed through the catalytic converter ( also called a catalyst monitor )
Just had my 2004 grand marquis convertor replaced (making an aweful noise). it cost me $250 for the part and then labor etc. total of bill for installing etc was $472.61.
It has one, it is located in the exhaust in front of the catalytic converter.
You can but the check engine light will remain on and it won't pass an emissions test.
On a 1996 Mercury Grand Marquis , 4.6 liter V8 engine : Bank 1 is the passenger side of the engine Sensor 2 would be AFTER the exhaust has passed through the catalytic converter
between the exhaust manifold and the muffler, closer to the engine though
They are in the exhaust pipe on either sides of the catalytic converter or converters.
There are two, one on each side of the catalytic converter.
where the starter located on a 1997 grand marquis