[HeyTeeee]

Hello All hope you're having a better day than me!
I'm having a real hard time for some reason wrapping my noggin round these o2 sensors.

By all means correct me please and thanks. Bentley manual says pre cat wiring harness is colored grey. I interpret pre cat as ...well before the cat. Real OEM tells me that this part no: 11787596924 is the pre cat. That is most certainly black. What am I missing here???

[weehe126]

Are you trying to figure out if you bought the right sensor? You can unplug the harness and make sure it plugs into the right one.

[HeyTeeee]

Originally Posted by weehe126

Are you trying to figure out if you bought the right sensor? You can unplug the harness and make sure it plugs into the right one.

Soon as I get that sucker unclipped from the back of the motor I’ll know for sure as Ill be able to see the whole wire. I’m more confused as to why the manual says it’s grey and mine isn’t. I can kinda see the grey one but not well enough to see where it goes

[HeyTeeee]

Grey one definitely goes to the post cat on mine. That pre cat wire was a real mofo to get unclipped. Didn’t end up using the o2 sockets I ordered just a 22m crows foot. Car didn’t sound happy starting up but I assume that is due to the dme relearning. Again x) Took it in a quick drive it feels fine ltfts were sitting -2,-3 which is better than -7 - (-9ish) it was creeping towards. I’ll do more driving after yard work to report back with results

[HeyTeeee]

I drove a bit even took a log bc it was beautiful out why not haha. Currently, afr readings after WOT based on 1 log hit 235 much quicker that’s an improvement. Timing corrections all cylinders are still *reasonably* ok. There appears to be something still holding the car back from running, also imo, healthy enough for any tunes. Ltft is sitting in the -5 range which is better than what is was after the injector swap...but I don’t feel enough driving and adaptation relearns have been obtained yet. 28A0 is still a pain in my arse as it likes to linger for a bit. I think that’ll be my next part swap. I’ll start with sensor on the intake since based on my log I took today, clearly reading boost just fine mayyyybe about 1lb psi give or take off target. If sensor fails to clean some of the issues up, I’ll double check plugs which are about 6 months old

[CoffeeBean]

You have them backwards. The pre-cat sensor has the black wrapping at the top and plugs into the connector nearest the front of the car. If you have that one in the pre-cat spot of the downpipe, just swap the connectors.

[HeyTeeee]

Originally Posted by CoffeeBean

You have them backwards. The pre-cat sensor has the black wrapping at the top and plugs into the connector nearest the front of the car. If you have that one in the pre-cat spot of the downpipe, just swap the connectors.

Are they? One of the connectors has 5 pins the other has 4 and they are currently connected that way 5to5 (black wire) 4to4 (grey).

[CoffeeBean]

Originally Posted by HeyTeeee

Are they? One of the connectors has 5 pins the other has 4 and they are currently connected that way 5to5 (black wire) 4to4 (grey).

The other end of the connectors on top of the valve cover must be swapped then, in which case they would be plugged in correctly.

[srrav1981]

You could have positioned them wrong on their little holder clips but the front/top sensor is the one with the metal shield around the cable close to the sensor itself to protect it from heat from the turbo. Its the 5 pin. the lower/downstream one is 4 pin. the color inside of the connectors matches each other, yellow for yellow, black for black etc.