I own a 94 Camry with a V-6 engine and assume you have either that engine or the 4 cylinder. I know the v-6 has two O2 sensors, one located in the exhaust manifold and the other near the catalytic converter. The autozone repair guide has a decent description, though I think there are other repair guides which give more detail. http://www.autozone.com/az/cds/en_us/0900823d/80/13/eb/c3/0900823d8013ebc3/repairInfoPages.htm
YesYes
The 2002 2.4L has 4. 2 on the exhaust manifolds, one before the catalytic converter and one after.
Toyota RAV4's have two (2) O2 sensors.
O2 Sensor.
2
should have 3. 1 on the front manifold, 1 on the rear manifold, and 1 on the mid pipe "center exhaust pipe"
video on removing O2 sensor: http://www.youtube.com/watch?v=ttUHqVz-sL0 technical info on O2 sensors: http://www.babcox.com/editorial/us/us10226.htm
That year has 2 oxygen sensors.
There are 2.
2
they are on your exhaust manifold, just before the silencer
check the O2 sensors