Chrysler Repair: 2001 Sebring coupe LXI 3.0 V6: 02 sensors, exhaust pipe, oil filter

Question
I need to know how many 02 sensors are on the 3.0 V6. I have already located 4 - under the hood there are two (one in the front and one in the rear between the firewall and engine). Under the car there is one at the exhaust pipe near the oil filter. And one in the rear going into the exhaust pipe. Is this correct?  I thought that there were only 2-02 sensors. If you could help me it would be greatly appreciated.

Answer
Hi Wesley,
I am certain there are 4 so you have found them all. The location of several are a bit different depending upon whether the vehicle was first sold in California or not. But if you count 4 those are correct. Two are needed for each bank of cylinders (up and down-stream)
Roland
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