I drive a 1999 Mercury Grand Marquis (70k miles on it) and recently noticed the oil pressure needle (far right on dashboard) not working. When I start the car the needle jumps very very slightly but it will not get past the C mark and it just sits there the entire time. All my other needles work except the oil one. I have no check engine lights or any other lights coming on. The car is tuned up, suspension work has been done, no leakage (just had an oil change). Could it possibly be a sensor that needs to be switched?