O2 Sensor num 2???

[Yulz9081]

Could someone please shed some light here. So at the perfomance place last week after the car was dyno'd it threw the engine light and when we ran diagnostics it said O2 sensor number 2 HEATING before CAT. So these okes insist its the sensor before the main CAT on the pipe and I need to replace it. I called Bosch, paid the R1425 and received the sensor yesterday, had it fitted today by the same guys but guess what, the light is back!!! :cursin:
Same story on the diagnostic machine.

So my question is, can anyone pin point on the E46 318i, which is exactly O2 sensor number 2???

My guess was number 1 would be the first one on the manifold and number 2 will be the second, so the one I replaced was Sensor num 3? For absolute F*ck all!!! I left the car there, told them do what you have to, I bought the sensor on their instruction so they fix it. I don't care what they have to do but my car aint leaving there until it is fixed and engine light off!
What a fcking morning.

 

[zaleonardz]

I hate the sensor replacing game....

Sorry for your troubles bro.

 

[Yulz9081]

Turns out it wasn't the sensor! It was the female port pins that were bent.
So I get charged for the auto electrician to go to their workshop,fix that and I'm out of pocket for
a sensor I didn't fcking need! I'm so annoyed but relieved at the same time that my car is sorted.

 

[rick540]

A note on sensors:

Bench test them first, an O2 sensor error can be caused by many things other than the sensor itself.

If you cannot test it or are not sure, PM me. I'm seeing guys waste a fortune on O2 sensors unescessarily daily.

 

[Yulz9081]

Thats the thing Rick, you gave some good tips on testing sensors. I just had no means of doing so and being busy with work I didn't have much time other than dropping and fetching my car.