Started getting a 'hunting' feeling from the motor while driving around town last week. Bank 2 O2 readings were showing a lean condition so figured I had an air leak. Smoke tested thoroughly and all the seals are tight, I have no vacuum leaks. At the same, the oxygen sensor stopped oscillating and now gives me consistent voltage with no fluctuations. Bank 1 appears to be working property. My conclusion is the bank 2 O2 has been fried and needs to be replaced.

I have the necessary tools but the major issue I'm dealing with is there's just not much room for leverage. I can get the O2 socket on the sensor from on top of the engine (an awkward reach to say the least) but I'm not strong enough with the breaker bar I can fit to get the sensor unfrozen. I thought about pulling the windshield cowling to fit a longer breaker bar but unfortunately there's an underside aluminum panel below the cowling. I could weld a 'bending' extension bar that would curve around the cowling to give me more leverage but that's work too and my welding skills are... rudimentary.

I think I need to go from below, but there's very little room to apply torque without removing the front prop shaft. So my current plan is to get all 4 wheels in the air and then remove the front prop shaft or at least reposition one side and use a scissors jack against a breaker bar to use mechanical advantage to unfreeze the sensor.

I've hit it with PB Blaster but I don't feel comfortable putting a torch on it, there's just so much other stuff nearby. I do have an induction heater, but I'd have to cut the sensor wires to get it over the nut which I'm not excited about doing but the downside of doing that is probably zero given that the sensor is messed up already.

Any advice from the community? I've watched the 2 youtube videos (one from Doug at Atlantic British and the other from a guy who went at it from above).

While under the car I checked out the aftermarket metal shield gas tank protector I installed in the fall when I did the rear differential. Looks great so far.

Thx,
- scooter

 

Sounds like a solution looking for a problem. Do you have fault codes present, related to the O2 sensor?

 

Maybe... I don't have any engine fault codes at all. I'll collect more data and give this additional thought before I go any further.

 

I applaud your efforts to keep your Rover in top notch condition. We often see them do things that make us say "why is it doing that?" and spend time trying to figure it out. There are enough things that break outright so as to keep me busy, I don't need to go looking for problems, they usually find me. IF the O2 sensor is out of range, it will let you know ( Codes). and then you can narrow your repair efforts. If it is in range but acting "funny" just keep an eye on it and plan the repair for a convenient time and place on your terms.

As for the process, I removed the front prop shaft from the front diff to get enough room to go after it from the bottom. On another one in the fleet, we later needed to replace the front diff, while it was out the left side O2 sensors were replaced having learned our lesson from the first adventure. Oh and I think they are 12mm reverse torx head bolts.

My best advice comes for the HAL 9000 computer when dealing with a AE-35 Communications Unit " I recommend you put the unit back in operations and let it fail"

Jeff