I change water pump an thermostat and when on xprsswy car runs extremly cold what could be the problem ?

i change water pump an thermostat on a 97 sunfire 2.2 and when on xprsswy car runs extremly cold an i lose all heat what could be the problem ?I change water pump an thermostat and when on xprsswy car runs extremly cold what could be the problem ?was the thermostat the correct one for your engine?I change water pump an thermostat and when on xprsswy car runs extremly cold what could be the problem ?You probably have an air lock in the cooling system and it is not full of coolant. It could be that the thermostat is stuck a little open or not seated correctly or backwards, but I rather suspect you need more coolant in your system. Park the car with the nose a little uphill and after it cools, check the coolant level.