O2 Sensor question

Compnewbie01

Senior member
Aug 8, 2005
603
4
81
I have pretty much determined that I have a faulty O2 sensor in my car. So, I found a guide on how to change the O2 sensor on my car quickly and easily. However, someone at work tells me that my car will have multiple O2 sensors and that any one of them could be the problem and that I may end up replacing more than one. The guide I found on Bimmer forums only shows one O2 sensor in the description and I wanted to ask if there are more than one. Any help would be appreciated as I need to get rid of this damn check engine light.
 

DivideBYZero

Lifer
May 18, 2001
24,117
2
0
Depends on the car. There are two O2 sensors in my M, AFAIK. One in each exhaust manifold. Your e36 may only have one manifold, so I would guess it only has one.

^usual caveats apply to this advice.
 

iamwiz82

Lifer
Jan 10, 2001
30,772
13
81
I'd imagine you have at least two, assumings it's OBDII, pre- and post- catalytic converter.
 

steppinthrax

Diamond Member
Jul 17, 2006
3,990
6
81
Most newer cars have 2 O2 sensors that is if it's and OBD-II system (mostly after 95). One in the manifold and one after the cat. If go to autozone or advance auto they have the exhaust diagrams. They will be able to show you how many O2 sensor you have and where they are located. BTW is it a 1 2 or 3 wire O2 sensor.
 

Compnewbie01

Senior member
Aug 8, 2005
603
4
81
Thanks for the replies. I don't know if it is 1, 2, or 3 wire, but I could probably find this out when I take the old out out.