'97 318is Oxygen Sensor
 

I need to replace the oxygen sensor on my '97 318is. I understand i need a special split extra long socket to do this. My question is... does anyone know where I can buy that? or what size it should be?

Thanks.

Right, you do need a special socket to get at the O2 sensor. Autozone, and I imagine other major chains, have free loaners, so drop into the nearest one.