1997 Toyota Corolla Rear O2 sensor needed?

MYXO

MEMBER
1997 TOYOTA COROLLA

1997 Toyota Corolla 4 cyl Front Wheel Drive Automatic 90K miles

Hey guys,

My rear O2 sensor broke off. I am considering not repairing it for now - should I just remove it completely or attach it to the car body so that it won't be hanging on the bottom? Is that correct, that this sensor only monitors the converter? Does this sensor affects engine performance?

Since it's broke off in the place where it was attached to the exhaust - how hard will it be to replace this part of the exhaust by myself with the sensor?

Also, how much should I listen to the mechanics, if one says that they can only change the sensor and the gasket (>300$) and another that they need to change the whole exhaust (>900$)? But both charging for the part >200 $ with the actual part cost $80.

Answers much appreciated,
Myxo

1 Reply

MMPRINCE4000

MECHANIC
8,549 POSTS

If the hex portion of the sensor is still intact, you can simply unscrew it and replace it. If the bung (the part welded to the exhaust is damaged), then you would only need to replace the portion of the exhaust from that point back to the next "break" in the exhaust (tail pipe for example).

It must be replaced, the engine will not run properly without O2 feedback, and can damage the convertor in short order.

Unless you have a MIG/TIG welder and the skill to use it, you could take it to a muffler shop, cut the pipe the sensor is in off, replace the cut piece with a pipe with a O2 sensor bung welded in place and weld the pipe back in place.