Hello all.
The post on O2 sensors has got me thinking. Mine are probably the original from when the car was made so my question is would it be wise to change them. I’m not sure what sort of signs a failing sensor would produce. You thoughts as always much appreciated.

Rob.

 

Failing oxygen sensors will usually show up in higher emissions and lower fuel economy.

If they are original, I would make plans on changing them. They aren't made to last forever. Without knowing the miles on your car, I can't tell if you're due, but I would at the very least acquire a set and have them ready.

 

Hi Vee. My car has around 60k on the clock. No problems with the emissions when it was motd in April. Tested with very low emissions.
Rob.

 

Leave well alone, Rob. But get a couple in the Christmas stocking so you are ready when they do fail!

 

Hi Greg. Thanks for the advise which is heeded. What would be the signs of a failure to look out for.

Rob.

 

Robbo
I think poor fuel consumption, ie overfuelling, plus MOT failure on emissions! But I know nothing about these things in a XJS. I think that, in some non-Jaguar applications at least, if they fail the ECU thinks the engine is cold and shoves in fuel as a consequence.