I bought the car with the sensor wires cut in the engine bay and didn't haveany engine lights on the display. But now after a year the yellow engine lighthas come on and the ODB reader says it’s the 02 sensor. Would it be best to reconnect these or is there a way around it

Thanks

 

Best to make good the connections and reuse the lambda! You'll be running rich in closed loop (off boost, below a certain rpm) otherwise!

And you'll end up knackering the cat (if still fitted) prematurely too.

And when it comes to MOT, if it's still dsiconnected, will fail on emissions big time.

So sort it.


Beggars the question: Why would the previous owner disconnect it by cutting the wires? Makes no sense; nothing to be gained.

Are you sure it's the wiring for the lambda, and not the EGT sensor instead?! When people decat, then the EGT isn't required, so normally the disconnected plug lies dormant in the engine bay somewhere (but obviously in this case the wires have been cut instead).