Switching the actual sensor looks like it will be easy enough if I can get access to it. A google search gave mixed results, some were saying the intake manifold needs to be removed whilst others said it was not necessary. I've had a look from underneath the car but I couldn't see it at all. Will check again tonight though. From what I can see removing the manifold should be fairly easy, just a bit faffy and time consuming. Have you done this before?