I am confused, when I start my car, the needle bounces then rests at 20mph. It will flutter until I get going about 5-10 mph, but stay at 20 the whole time. Then randomly it will shoot up and read the corrext speed. Then the next time I start her up, the same thing happens. This didn't start until yesterday, it has been unseasonably cold here in Tennessee, but it got up to the 40's yesterday, when it all started. Do you think the cold has something to do with it, or the fact that my chassis and about all electrics have 170k on them. Anyway if anyone knows what the hell is wrong, let me know please.

P.S.- Since the cold weather, my fuel gauge is now reading full when it used to only go up to about 3/4