I got this reading on my OBD code reader "0432 Main Catalyst Efficiency Below Threshold (Bank 2)" What is "Bank 2"? I know that "Bank 1" for the O2 sensor is before the cat and "Bank 2 is after the cat. but how do I identify which cat is it if theyre side by side?

 

Nope, not quite...

Bank 1 is the 1st three cylinders
Bank 2 is the 2nd three cylinders

When facing the motor, bank one is on the left (passenger side) and bank two is on the right (driver's side).
Thus, the system is saying that your problem is located on the driver's side down pipe.
Sounds like you might have an exhaust leak

 

i have a 6cyl. im pretty sure its the same right? 1st 3 cyls is bank 1 and last 3 cyls is bank 2. is that code common for exhaust leaks?