If you are bringing this up because you suspect a knock sensor problem--I have a test-but I don't know if it's truly an accurate test. In my quest to develop a little more sophisticated water injection system than my original simple-all mechanical system-I removed the knock sensor from a couple of junk Volvos and Saabs-set them up in a vice and tapped on the vice lightly with a hammer. They were showing about one half a volt with a multimeter hooked up. BTW Andrew--your window regulator and door handle are on the way. -- Dave