Hi! My name is Iain and I live in London. I was the happy owner of my x Reg 4.00 coupe xk8 until my engine light came on and after half an hour driving it's the limp mode comes up on the dash and she is restricted.

I had it diagnosed and the code was for the post cat Lamdor sensor. I bought a Walker product but that has done nothing to help. The original one is a Denso, so I’ve now replaced it with one but it still does not sought the problem.

I’m at a complete loss. HELP!!

(Cheers)

 

You need to re-read the codes, once we have those we can point you in the right direction

 

Hi Iain post up the diagnostic code if you know it please,it will be helpful to anyone viewing the post

 

Hi there and thank you for your help! The code from the car is P1647. I hope this may help! Thank you!

 

It is a sensor code, does your CATs have 2 or 1 sensor, later cars changed to a 2 sensor CAT cant remember off the top of my head what the change over year was but was somewhere around that time I beleive.
If is a single sensor you will need to check the wiring, the plugs can be a bugger to get at and maybe a wire has been pulled, failing that it could be a ECM failure but unlikely, I have never had one go on me yet.

 

I think X reg has upstream and down stream sensors - PO1647 is B bank upstream. Either, heater failure, short to ground or high voltage, sensing circuit open circuit, or ECM failure (highly unlikely!)

No wonder it's still there, they've replaced the downstream when it's the upstream.
Hope that helps!

 

Could it possibly just be that the codes need to be reset?

 

not if the wrong sensor was replaced, it will remain until it's replaced, then a reset.

 

Hi again! Thank you for your replys. My car has two sensores on each side, post cat and pre cat. Hope that helps. Thank you!