if only P0420 no other code, 95% sure CAT CONVERTER

is bad. NOt O2 sensor issue. You spent $400 ( labor+ part), it must be a rebuild one. Brand new part usually costs $800+ . Some local shops use very cheap parts, they turn bad very quickly. Best solution is buy a cat converter from auto zone (about $100 3 years warrenty) and let your local shop install it for you.

所有跟帖： 

• there is an old P0446, it showed before the 0420. -majia01- ♀ (0 bytes) () 09/09/2010 postreply 12:30:48

• P0446 is a little tricky -nonego- ♂ (275 bytes) () 09/09/2010 postreply 12:59:38

• i already put aside $400 to fix it -majia01- ♀ (47 bytes) () 09/09/2010 postreply 13:37:38