i put in a mechanical temp gauge my heater core sprung a leak put a new in. I was running at the most 185deg in town on the highway about 165deg replaced the thermostat it was a 180deg with a 195deg. so it gets warm now but now i have no heat it cold. what do ya think I think there might be an air pocket thats about the only thing i can think of. I pressure tested it. and i got 3/4 of the radiator covered and it will just not get hot enough im going to be driving through a lot colder weather than here so if it runs that cool now its only going to cooler. so what do ya think. help would be greatly apprciated.