My brother has a 2006 Toyota RAV4 with 125,000 miles, which we think has a clogged heater core. The Toyota maintenance schedule calls for changing the coolant every 100,000 miles, which he has done.
The heater core is a small radiator that warms the car’s cabin using hot coolant from the engine. The cooling system’s hoses circulate liquid coolant through the heater core as they do through the ...