Ford O2 sensors, same or different?
I noticed on the 2001 expedition I bought that it looks like they put an O2 sensor with the long cord before the cat. All the ones online say the long cord is the back one.
There is conflicting info online. Does it matter, are all o2 sensors the same? Before cat, after cat doesn't matter?
2 replies
Yes and no. Most Oxygen sensors are basicly the same with various lengths of wire and connectors. That goes for upstream (helping adjust air/fuel mix) and downstream (monitor catilyst)
Whats gonna get you is the Air/Fuel ratior sensors the newer cars are using upstream. These actually send an opposite signal from a traditional O2 sensor and isn't cross compatible.
Funny thing, I moved from the automotive world into industrial burners and discovered even those big burners are using pretty much the same O2 sensor you find under your car's hood.
It depends.
Before and after cat can have different reporting requirements depending on the system.
I'd look into the EFI system that vehicle uses to know more specifically.
You'd probably do better on a forum for that specific car - those folks tend to know really crazy specifics.