An air bubble in your car's heater core may not cause many problems during warmer months, but it can be dangerous once the temperature dips below freezing. There are several signs and symptoms that you may notice if an air pocket is trapped in your vehicle's heater core.
The heater core is what produces the heat for your heater. If there is an air bubble in your heater core, then it may not be able to generate enough heat to warm the cab of your car.
Air bubbles can form when there is not enough coolant in your cooling system. If there is an air bubble in your heating core, you may notice that your coolant is a bit low when you check it.
Air pockets in your heater core will impede the flow of coolant through your car's systems. If the air pocket is large enough, or combined with low coolant levels, the engine may overheat.
