On the 4.0 liter OHV - V6 - I believe there are ( 3 ) on a 1996 Ford Explorer
2 that are used for the air / fuel mixture that are before the catalytic converters
( upstream ) and 1 after the catalytic converters ( downstream ) that is used as a
catalyst monitor
Dealership or any auto part store.
4 ======================================================= The above answer is correct if you have the 5.0 liter V8 engine in your 1996 Ford Explorer , but if you have the 4.0 liter EFI , V6 engine ( VIN " X " ) there are ( 3 oxygen sensors )
The oxygen sensors located before ( upstream ) of the catalytic converters are used to " sense " the amount of oxygen in the exhaust to adjust the air / fuel ratio for the engine
I have a 1996 cadillac deville concours, an it has 4 oxygen sensors
All oxygen sensors are threaded into the exhaust system.
The 5.0 liter V8 has ( 4 ) oxygen sensors The 4.0 liter EFI ( which is an over head valve / pushrod design ) has ( 3 ) oxygen sensors Note: The 2 upstream oxygen sensors are used for adjusting the air / fuel ratio of the engine , the other oxygen sensor (s) are called catalyst monitors and monitor the performance of the catalytic converter(s)
The oxygen sensors on a 1996 Chrysler Town and Country are screwed into the exhaust system behind the engine.
they are part of the hub assembly
My Chilton repair manual engine wiring schematic, for the 1996 Ford Explorer with a 4.0 L OHV engine shows 3 . Two are upstream (before the catalytic convertor) and one downstream (after the catalytic convertor - which is an oxygen sensor but is used to monitor the efficiency of the catalytic convertor)
two
two
4