[Musclecars4l1fe]

I'm having an issue with my tach and speedo not reading correcty. They both work as does the odo, and trip they just don't read correctly. I have looked through here for a similar problem to no avail. If anyone has encountered this problem or know of a thread for it already. Please enlighten me as to what is going on. I have searched else where and all I can find is the units themselves need to be replaced.