speedometer tempreture/fuel problems

random problem

after discussing with a mate how cold it is outside we decided to check

got into my car and it was showing -40 which is defiantly not correct

so a few hours later got into my car and it slowly went back to normal tempreture

so after driving I noticed the fuel had suddenly dropped and so was the tempreture

when I restarted the car the fuel had gone back up

what would the problem be caused by