The O2 sensor on a 1988 F250 is not near the engine. Go to the exhaust manifold and down the length. It is near the catalytic converter.
Diesels do not use oxygen sensors
#1 cylinder is on the left side so bank 2 is the right side sensor 1 is before the cat sensor 2 is after the cat
I'm not a mechanic / technician but on a 1988 Ford Ranger there might be ( 1 ) oxygen sensor ( upstream sensor )
check the O2 sensor
Standing straight up in the drivers seat.
Yes. It's located in front of the catalytic convertor.
02 sensor is either in exhaust manifold, or in exhaust pipe between manifold and muffler
It is screwed into the exhaust manifold behind the engine.
o2 sensor fuel too rich
there should be a couple of them screwed into the exhaust system.
On the exhaust pipe, from where it leaves the engine, but before the catalytic converter.
Depends on what the problem is or what code was set.