Catalytic Converter issue

[Jninja]

Hello everyone, I am in need of serious help,I have a 2001 Pontiac GRAND AM GT and I am getting a code"Catalytic Efficency Below Threshold" My converter has already been changed twice along with my oxygen sensors, Can anyone point me in the right direction--Thanks

 

[Unregistered]

2 cat converters is way too much,what plugs up a converter is the rich exhaust. sounds like you've got a computer rich/lean mix problem. don't fix symptoms fix the cause of it.