Why the Light?

[CoryCD8]

Ok....my check engine light came on. Went and got the code which was P0420. That means: Catalyst system efficiency below threshold(Bank 1). Does this mean I need a new cat or what? Please help cause I don't want to spend $315 for a new one.

[Rookie]

I had the same code and it was caused by an exhaust leak at the converter flange. If you need a new converter by an after matket one from some place like summit racing,,, summitracing.com. if its a newer truck have it covered under warranty should be 8yr/80000 miles federal emmision warranty.

 

just my .02