there are 4 on the car 2 in front of the cats 2 behind the cats on the exhaust pipes
You have several O2 sensors on that vehicle and they are all threaded into the exhaust system at various points.
2
The '97 is OBDII. There are 4 different O2 sensors on the '97 Cadillac. http://www.airbagcrash.com
All O2 sensors are located in the exhaust system at various points.
i believe there are 2
The O2 sensor on any vechicle will be located on the exhaust manifold.
Pre or Post?
YES
you have 3 on the astro & safari vans 4.3L
one at the front of the cat and one after the cat
Two, one on each side of the catalytic converter
I have a '95 E150 and a '96 E250, both are 4.9 straight 6 cyl. One has 1 O2 sensor and the other has 2, one on each half of the exhayst manifold. I believe the 96 has 2. but it is an E250, not sure about the '96 E150.