I own a 1992 SC. The tachometer goes up and down from 2,000 rpm to 4,000 rpm, with of course, no change in the engines idling. I read from another thread that the tachometer probably needs to be replaced. I called Ford in my town and they said that the part is no longer available and they can't get one from anyone else. They told me to get a used one and that it had to be from a 1992 SC. Thanks for nothing Ford of Sioux Falls. Anyway I am hoping someone out there can help me determine if I can use a tach out of any year (89 to 95) SC's or do I have to find one specifically from a 92. If you know the answer to this and have one for sale let me know as I will most likely buy it. Thanks.