o2 sensor code but it still works?
 

I have this strange issue where i get code for my o2 but i still manage to do about 40mpg. is this what causes my mpgs to stay this low? My car is a vw polo from 2000 with 1.4 mpi engine.
error - Album on Imgur
i will be doing a roadtrip soon and i dont want to kill the cat :p

EDIT: sorry for any mistakes i made. im trying to save as much money as possible and im trying to learn

I do not know. About once a week I get an error code for my oxygen sensor, which I replaced with the correct OEM one because I was receiving the code. I just clear it and the car seems to drive fine.

i clear the code and then it says code pending and later it turns into current fault again.

The chart linked to would be more helpful if you could increase the range from 0.43 - 0.434v up to 0.0 - 1.0v.
Does it make it into closed loop, at least at times? Fuel trims less than +/- 10%?

i tried it again and it auto ranges. so it is actually stuck between those 2 values. that means it is broken after all. it drives normal, the fuel economy is not horrible and there is not much black stuff in the exhaust.
The car will make a long (400 mile) trip soon.

EDIT: i will check if it goes into closed loop. i will also disconenct the o2 cable and read it with a volt meter.

EDIT 2: the fuel trim is at 0% it never goes into closed loop and the o2 voltage when hot reads 0,4x volt. I order one from aliexpress cus i am cheap basterd:p