Hi, when I turn on my car and start driving the odometer goes to + 140 mph and stay there about 10 or 15 minutes (the real speed is about 35 - 40 mph), after that, it return to normal but sometimes it hits again the top of the scale, it continues doing that for about 10 minutes more, so I lose my odometer for about 25 minutes. I really need to fix the problem asap. Other thing, it sometimes shows an incorrect speed (45 when i'm driving at
35). HELP!!!!. Thanks. Jonathan.