When i turn my car on the temp gauge goes up to hot even tho the e gines cold. It goes back down for a minute then rises again. First snow of the yr today and my heat wont work either whats wrong?

A few things. Check your coolant level and make sure the system is full. You may have air pockets making you gauge jump around. Low coolant level will also cause problems with your heat. Verify the cooling system is building pressure and the thermostat is functional. Squeeze the top radiator hose after the car is up to temperature. If you can easily collapse the hose, the system is not building pressure and you could have a bad thermostat or faulty radiator cap. If all of this checks out, the temperature sensor itself could be faulty, but with no heat, I'm thinking there are other problems.

The symptoms sound like a thermostat problem. Change the stat, should solve your problem. Have the radiator cap pressure checked too. Should be around 14 psi . Also have the temp of the coolant tested too. should be a 50/50 mixture, good to about -34 below. If in a colder state, 70% is normal.