[Jak90]

Hi guys kinda new on this forum,just have a question regarding specs above, I have engine management light come on, reset it and came on again after couple days, it came up nox sensor short circuit. I've read up about reviews but I haven't had any codes for misfires etc, the car only done 35k, just got it serviced hoping new plugs may improve things, but not really,

The car drives okay nothing too drastic but wound earring if it's only matter of fact changing the sensor and resetting ecu ?? Been qutd £630 all in. But I was wondering is it the sensor or sis it something causing the sensor to cause this???