|
I doubt that the 14.5V is the problem, there'd be a lot more reports of it not working if that were the case. The voltage regulator is designed to take anything over 5V, and output an even 5V for the entire board, and output the rest of the energy into heat.
A new ground couldn't hurt. Also, do you know if the VSS signal from the ECU is the same one that went to the speedometer? If it splits anywhere, then I would try tapping it right from the ECU.
__________________
|