Accord check engine
 

hey guys my check engine came on code P0420 catalyist system...someting. so they shop changed the O2 sensor on the top and my check engine came back on again..i don't know what to do i have 60k on my car could it be my cat?? if it is do you guys know if it's still under warranty or not?cuz i heard that cats are covered for 8 year 80000 .. by the way its a 1998 4cyl auto.

A P0420 is indeed a cat. there may also be a melted secondary O2 sensor. Both of which are covered under 8/80 warrenty.