Oxygen Sensor(s)???

Hey, everyone! I'm new to this forum but i figured if anyone knew the answer... you guys would.

How many oxygen sensors are on the 626 LX (1998) and where are they?

which engine?? the four banger only has one, and is in the header pipe. Later, mark.

My 95 V6 has two. They are easy to replace with an O2 sensor socket, but the sensors cost $170 a piece. Make sure you put the one with the long pigtail in back. (I accidently put it in front and had to take it back off.)

OBDI has one per bank.
(all in downpipe)
OBDII has two per bank.
(one in manifold, one after warmup car)

02S11 = bank 1 upsteam
02s12 = bank 1 downstream
02s21 = bank 2 upstream
02s22 = bank 2 downstream