2003 Montero Limited

Oxygen Sensor-

Anyone have a part #? Also, can I get to it from underneath the car, or just under the hood? I've been told I need a special wrench to do it so I don't harm the wires. Sorry if this is a stupid question, I've never had a car long enough to have an oxygen sensor go bad.

 

P0155: O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)

I do know that this is the downstreat (after cat) 02 sensor but I am not sure which one [sm=alcoholic.gif].I have read that you should replace both rear sensors if you are replacing one. Go to autozone.com, they are about $75...make sure you get the OEM that will plug right in...cause the "universal" will require soldering. Yes you will need a wrench for it, but I don't know more about that.

I am in the process of getting everything together to replace my downstream 02's.

 

Everyone I've talked to says there are two upstream, and my fault code is before the cats. The truck only has 39k miles, I thought they lasted longer than that.

 

So what code do you have? If you have P0155 as indicated before, it is a sensor AFTER the cat (Bank 2). You do have 2 upstream (pre cat) O2's...but you also have two downstream O2's (post cat).

You need to post the code that you are getting from the car.

 

Sorry- Bank 2, Sensor 1

I haven't even been underneath the truck to look, but I assume there is a right and a left one behind the cat?

I had planned to order from these guys unlesss someone here knows a better place.

http://oxygen.ecatalyticconverter.co...=Oxygen+Sensor

 

From everything I've been reading about 02 sensors, it says that the Bank has to do with what SIDE the sensor is on, not whether it is before or after the cat. From there, the sensor # would be according to where it is in proximity to the engine, 1 being the closest, 2 being before the cat, 3 being after etc....

 

https://mitsubishiforum.com/m_103545/tm.htm

This should help...

Sorry about my confusion, I have had 0157&0159 and it is B-2 S-2...I confused myself lol!

 

Now all I need to do is find out which side cylinder 1 or 2 is on!??



How can I find out which cylinders are on a given side? I didn't see anything on the wires or valve covers.

 

Bank 1 is on the pass side and bank 2 is on the drivers side


Bank1 Bank2

5 6
3 4
12




Front of car

 

Thanks- I found that link shortly after I posted- Ordered the part, should be here this week.