2004 Toyota Corolla oxygen sensor fix

I drive a Toyota Corolla S 2004 and its at about 275000 km. About a month go the engine light came on and when I had it checked the mechanic told me it was the oxygen sensor. at the time he gave me a quote of $350 to fix the problem but reset the engine light and told me to come back if the light comes back on. while driving today the light came back on, so I am wondering if the oxygen sensor is worth the $350 to fix .

The light is there for a reason. If it is lit, the car needs service. The O2 sensor is used by the car to help it run correctly. If it isn’t working, the car does its best to keep running but it will not be optimal and it may cause further damage if not repaired.

Now $350 seems a bit much for an O2 sensor so I’d call around to other shops and see if that price is reasonable.

No offense, but until you have the codes rescanned, you have no idea if the light is on because of the oxygen sensor . . . or something else entirely

If you live in an area with smog inspections, the $350 is definitely money well spent

There is no guarantee that replacing the oxygen sensor will fix the problem, assuming the error code is the same.

It could be the wiring to the sensor, or some more subtle problem. The error code is just a guide for where the problem may be.

There’s two O2 sensors on the 1.8L 1ZZ-FE engine. Parts cost, front appx $150, rear appx $200. A little over 1 hour to replace one of them, so $350 seems pretty reasonable. That’s assuming you actually have an O2 sensor related problem of course. Good idea as mentioned above for you to post the actual diagnostic codes and see what the folks here think first. There’s a lot of unnecessary O2 sensor replacements done.

The front O2 sensor is used to set the proper air fuel ratio. Too lean or too rich could cause drivability problems or even engine damage, so if it is front one, best to get that dealt with expeditiously. The rear one is to verify the cat is working properly. Downsides of not fixing that one are the possibility of excessive emissions, failing to pass a smog test, and/or a plugged cat and a stalled car.

Note: There’s a customer interest bulletin on this car for code p0133. The fix for that isn’t to replace the sensor, but to re-flash the ECM. Refer to bulletin number: EG017-7. You might be able to see a copy by googling that number.

I agree with everyone else that the OP should go to autozone and have the code read.