Hey guys, thanks for this thread I just read the entire thing. My moms car is getting a Cel
P0431 Warm-up catalyst system (LH) efficiency below threshold ON 2 Catalyst
So I bought a new 02 sensor just in case but I think I may try this 1st because I got a 3 wire universal 02 sensor and it looks like i'll need the 4 wire..
My question is I know the car has 4 02 sensors. which one is bad? I take it LH means left hand side, is that standing in front of the car or in the drivers seat left hand? Also it as mentioned to do this to the 02 sensors after the precat converters? does anyone have any pictures or diagrams? Do you do this mod on the 3 wire front or 4 wire rear or dies it matter? Sorry I am all confused. I have been looking at mazda forums all day and I still dont know. Thanks