oxygen sensors, an interchangeable part?

Some are interchangeable but the part number must be same.

I appreciate the response KHLow2008! But so how would I know which cars might have the same oxygen sensors as mine? Would it definitely need to be a Mitsubishi or what?

Also the subject line of my question says it is a 4cyl, but it is not. My car is a 2003 Mitsubishi Eclipse 3.0L V6. I don't know the 2 letters after the word Eclipse, but I definitely know it is a 3.0L V6.

Yup, it would have to be from a Mitsubishi and 4 or 6 cylinders does not matter.

Sorry I am not able to tell you the sensor can come from which exact model. We too have problem figuring this out when we try to get the replacement from junkyards. If you are getting it from the junk-yard, they should be able to tell you or at least get you the correct one.

Ok thanks so much!

Oh I forgot! Do you know where P0135 Bank 1 Sensor 1 and P0141 Bank 1 Sensor 2 are located on my 2003 Mits. Eclipse 3.0L? It would be great if I could see a picture or diagram!! Also how many sensors does my car have altogether?

There are altogether 4 O2 sensors.

P0135 is the right bank front sensor, meaning the cylinders on your right hand side when you look at engine from the pulley end.
P0141 is for the same bank, rear sensor.

Sensors are screwed onto the exhaust system. Front sensor would be just after the exhaust manifold and the rear sensor would be after the catalytic converter.

I could not find any diagrams to show you but the link should be better.

http://www.youtube.com/watch?v=LFR8Numjy7M