Hello everyone, I’m new to the forum and the new owner of a 2006 Montero 3.8L with 230,000 on it. Maintenance on it had been neglected for a long time, but I’m slowly bringing it back to life. I have finally stopped all the oil leaks (I think) and got the CEL off by doing valve covers, rear cam o-rings, butterfly valve shaft o-ring, and all new oxygen sensors. The only thing I have left for this job is the b2s1 (drivers side upper) oxygen sensor. I can’t for the life of me figure out how to go about removing it. I had to use a breaker bar on the others, and I can’t find a way to get a wrench in there to even attempt to turn it. Any help would be greatly appreciated!



Here she is! Up next I’m tackling the flashing 4x4 light and front differential fluid change. I have replaced the freewheel clutch switch, but I believe my problem is the actuator itself. I plan to post anything interesting or helpful that I find out along the way that hasn’t already been covered.

 

You will likely need to get an , you can rent them at just about any major parts store. You'll get every penny back when you return the tool or you can just keep it and after awhile it's yours. I don't have any experience with the Monteros as I'm a sport owner, but man that Montero looks nice.

 

I’ve got a couple styles of o2 sensor wrenches, they definitely help. I just have no room going at the sensor from below. Was just hoping someone could chime in who has changed it before. I’m thinking I can remove the oil and transmission dipstick bracket and the heat shield below that and get the sensor from above, hopefully..

 

It is a tight spot down there ion Gen III Montero. You can drop front driveshaft. If that still does not create enough clearance, remove entire Y-pipe and deal with that sensor outside the vehicle.