Since the 2018 Hyundai Tucson doesn't have a radiator cap, is there any way to get rid of any air that's trapped inside the cooling system? My wife's 2018 Tucson with the 2.0L, has terrible heat in the winter, as many of you probably already know. We live in Upstate, NY and the winters can get brutally cold. We had the dealer replace the thermostat already, but there was no change in the heat output. In the past, I've "burped" (bleed) the coolant system on a few cars, which released a lot of trapped air bubbles, which improved the heat output. Could trapped air be causing the poor heat output coming from these engines during the winter? Does anyone know how the dealer bleeds the coolant system on our vehicles?