Even though the warm weather hasn’t heated up yet, it’s time to think about keeping cool in your car.

If that seems premature, think about the last time you drove by a disabled auto in the dead of summer heat. Chances are good that if engine overheating caused it, the fix would have cost about $15 to replace a hose to the radiator system. Compare that with the $1,500 to $3,000cost of repairing an overheated engine with a blown head gasket, and the reason for urgency is clear.