2005 Taurus. 82K miles, 3L, 6cyl, OHV engine, auto transmission. Occasionally the tachometer goes crazy. When this happens, it seems like the car loses some power. The reading on the tach is definitely incorrect when this happens (needle all over the place). I was wondering if anyone has had a similar problem and replaced something called the “speed sensor” ??? Couldn’t find anything else that this problem may point to ??
I agree with your thought about the speed sensor being the issue. Check for a bad connection to it also since it is an intermittent problem.