EM light and Oxygen sensor

The EM light on my 2.2 VX220 came on recently and is staying on. Local VX
dealership popped it on to Tech 2 which diagnosed the oxygen sensor as
needing replaced. During the trip back from the garage, without the work
being done [no sensor in stock], the light went out itself. Question is
does anyone know if it is "cured" or does popping the Tech 2 on to it clear
the error from the memory until it reappears?

Thanks

Ian

 

they typically suffer doggy connections as they are bolted to the front part
of the exhaust and get bashed if you run over sticks or WHY.
pop under the car and inspect the wires going to it, make sure they are not
stripped and touching each pother.

there are other reasons why your car will show an O2 failure, of which the
dealer should of been aware.
there is a known earthing problem with them.
its on one of the other website threads.

TBH i would ignore it till it [if it] comes back.
and yes tech2 would clear the fault if told too.

mike