Replacing post-cat O2 Sensor

[willbishop123]

Hello,

I have just recently purchased a Z4M with 44K on the clock, and after a few miles later the emission check light has has come on. After further inspection and fault reading it turns out that the fault is with the Bank 1 O2 sensor (located in the cat). I have bought the replacement part and need some advice on how to remove the old one and then fit the new one. So my question really is, would I need a unique socket in order to remove and fit the sensor or can a spanner do the trick?

Thanks.

 

[fatmikey]

Welcome! As the sensor will have been in there for many years its likely to have siezed in & a spanner will end up rounding the edges off.

The easiest way in my opinion is to heat it up with a blow torch then use mole grips to remove it, thats the way i removed mine. As its already knakered the heat wont do any harm

 

[Half Colin]

On my Corsa Bank 1 is before the Cat and Bank 2 is after the Cat - not sure about the Z4 but would have thought it would have been the same. :erm:

 

[willbishop123]

On my Corsa Bank 1 is before the Cat and Bank 2 is after the Cat - not sure about the Z4 but would have thought it would have been the same. :erm:

Im not sure, the printout is stating the problem is after the cat. I think bank 1 is the first 3 cylinders of the engine nearest to the rad. Though I could be wrong.

 

[fatmikey]

bank 1 is the first 3 cyliners & bank 2 is the last 3 cylinders, if your unsure which it is then unplug the sensor & see what fault it brings up, if its not the correct one, unplug the next one

 

[chris53z4]

On my Corsa Bank 1 is before the Cat and Bank 2 is after the Cat - not sure about the Z4 but would have thought it would have been the same. :erm:

Hi guys,

The bank is referring to the cylinder bank for a 'V' engine for example. The sensor number will correspond to its position i.e. bank 1 sensor 2 would be the exhaust from the bank with pistons 1-3 in (bank 1) and sensor 2 would be post cat (sensor 1 pre cat).

The sensors are generally very tight but if you heat them up, just with the engine often, they will come out. Screw in the new one and plug it in. You will need to reset the fault.

Goodluck.