Some sensors give totally the wrong value of resistance at given temperatures, making them useless. The temp sensors can govern quite a few things further down the line, so can throw many other settings out. So it is important to make sure the replacement is true/accurate. On a temp sensor purely for a dash gauge its not so critical, as it may under/over read, but as long as you know its at the 'normal' position /right temp and not over heating, fans work but hardly get used etc then its ok. On an ecu/wur etc reading sensor its far more important
