Firstly I am surprised that almost all the info here is for first and second-gen Foresters. That said in the quest to engage in some preventative maintenance, I tried to remove my upstream O2 sensor ( technically air-fuel sensor), and the mother will not budge, and my O2 socket is rounding it off.
I did as the service manual instructs and disconnected my right side engine fan so that you can angle a couple of long extensions down and get at the O2. But despite lots of liquid wrench, it was no go. I did it with the engine and exhaust cold, but I might have to try with it hot.
My question is should I just try to bust the sensor so that I can get a short 6 point socket on it? I don't like using heat and am not too sure how you would in any case unless you drop the whole exhaust. How hard is it in fact to drop? That might have to be the other alternative.
And it's no longer preventative maintenance after my failed efforts, idle is rough, code P1153 and despite clearing that and doing an idle relearn idle is still too low and wants to possibly stall. The car has 260,000 km, the sensors were original, and while they were not giving off error codes I figured they were on the downslope and it would be a question of time
I did as the service manual instructs and disconnected my right side engine fan so that you can angle a couple of long extensions down and get at the O2. But despite lots of liquid wrench, it was no go. I did it with the engine and exhaust cold, but I might have to try with it hot.
My question is should I just try to bust the sensor so that I can get a short 6 point socket on it? I don't like using heat and am not too sure how you would in any case unless you drop the whole exhaust. How hard is it in fact to drop? That might have to be the other alternative.
And it's no longer preventative maintenance after my failed efforts, idle is rough, code P1153 and despite clearing that and doing an idle relearn idle is still too low and wants to possibly stall. The car has 260,000 km, the sensors were original, and while they were not giving off error codes I figured they were on the downslope and it would be a question of time
