P0420/p0430 是一回事，四缸車就是420， 六缸則可能兩個都有

建議去這裏看看，http://hubpages.com/autos/Catalytic-Converters-For-Dummies

 

Here is a huge secret that has not made it into the public domain yet:

If you remove a rear oxygen sensor and pack it with red RTV silicone, that will destroy the oxygen sensor in a way that will trick your car's computer into thinking the catalyst is okay. The sensor will not work well enough to report that extra oxygen is coming out of the converter, but it will still generate enough voltage to pass the car's oxygen sensor activity test. Never do this to a front oxygen sensor because it will mess up the fuel system.

其實就是死馬當活馬醫。

一般來說，下遊的o2 sensor 是匯報Cat 狀態的。先拿矽膠蒙上試試，不行再換新的。

盡量不要換cat, 太貴了。

所有跟帖： 

• 先換了上遊氧氣感受器後觀察2,3周看引擎燈會不會消失，不行的話再試試您的方法，謝謝！ -sillywoman- ♀ (0 bytes) () 02/16/2016 postreply 19:12:08