Toyota Repair: Tercel Dash vibration, speedometer needle, tercel

Question
Hello, When It gets cold or cooler in the mornings, and I am driving my 1992 tercel there is a high pitched vibration that is causing my gas needle to bounce and the speedometer needle to go way past the 110 mph that is listed on the guage. Now I would love to believe that I was actually doing 110+ in a 1992 Tercel, but I know thats not the case. It was actually pushing the needle so hard the needle broke in half. Any ideas of what could cause such a strong vibration? If it helps there is no additional strain on the engine or the car, but it is getting annoying and I am a bit worried there maybe something major wrong.

Answer
The only thing I can think of is that there may be a problem with the motor mounts although I have not seen a condition this severe, have motor mounts checked, I have no idea why the speedo would go up that high but I would recommend having the mounts checked.