I think one of my O2 sensors is going bad and I want to swap them side to side to be sure.
Where do the O2 connectors connect?
thanks

 

The mount bracket is on the top of the gearbox just aft of the bell housing.

They are color coded grey and black.

bob

 

Which O2 sensors? Unless it’s an early Uk car, then there are 4 sensors. The two up streams are located on the bulkhead under the throttle body.

you can see what they’re doing with an OBD reader before you change them.

 

Yeah, I can see where the greys go but not the blacks. DO i need to remove throttle body to get to them?
2001 xk8
How do I get under and behind this block?

And then when i was snaking my hand down there this piece came loose. What is it?

 

So I got the passenger side lower O2 up and read DENSO O65500-4961 O7B12 on it. Is this same as 234-4798?

 

That is a water shield for the gearbox breather behind the O2 sensor mount bracket.

 

Thank you Bob.
I will go look at parts diagrams for it.

 

I removed the throttle body to gain access.
Then I was able to move that big junction block aside to see where the connectors are.
Then disengage them from mounting block to remove connectors.


Bob, I see a flexible rubber shield behind the connectors.
The piece I pulled out was hard plastic. I cannot find it in any parts diagrams.

 

The connector for the passenger lower sensor is routed behind a bunch of wiring back in there and cannot be extricated.
Having to do all this to get to connectors, I am not going to do the swap I thought. So I have ordered all four and will do that next weekend.

 

Well, after much effort I was able to extricate it from behind the coolant hoses that run just under the firewall.

 

I have the 4 new sensors. I cannot apply correct torque for installation.
So I removed the central muffler section. Just follow JTIS instructions, not hard, and the section is not very heavy.
Then cut the O2 sensor wire tie wraps now or you will have some choice words later. Then undo the catalyst bolts and lower each.
Then you can install the O2 sensors. This all took about 1/8 the time for me to extract the first O2 sensor