What could be wrong if you are getting a p0420 code on 1999 Mazda protige?

A P0420 code on a 1999 Mazda Protege indicates that the catalytic converter is not functioning properly. This could be due to several factors, including:

- A faulty oxygen sensor is sending incorrect signals to the engine computer, which is causing the engine to run too rich or too lean.

- A bad catalytic converter is not able to properly convert harmful emissions into less harmful ones

- An exhaust leak is allowing oxygen to enter the exhaust system, which is causing the catalytic converter to work improperly

- A vacuum leak is causing the engine to run too lean, which is causing the catalytic converter to overheat

- A clogged fuel injector is causing the engine to run too rich, which is causing the catalytic converter to overheat.