water temp gauge
 

ok i just got my gfs beetle back up and running and i installed a water temp gauge and i wired all the wires according to the instructions and i grounded the adapter(t fitting) but when i turn the car on the temp gauge flips out to 250 and stays there, i unplugged the ground and the gauge drops all the way down but it doesn't move when the car warms up, i am at a loss thank you in advance