Blown Head Gasket: Signs, Causes, and What to Do Next

When your engine starts acting up—overheating, losing coolant, or puffing white smoke out the exhaust—you might be dealing with a blown head gasket, a sealed component between the engine block and cylinder head that keeps coolant, oil, and combustion gases in their proper places. Also known as a head gasket failure, it’s one of the most serious yet common engine problems drivers face. This isn’t a small leak you can ignore. A blown head gasket lets coolant mix with oil, lets combustion gases escape into the cooling system, and can lead to warped cylinder heads or even a seized engine if you keep driving.

The engine overheating, when the cooling system can’t remove heat fast enough, often triggers head gasket failure. It’s not always the cause—but it’s the biggest contributor. If your radiator is leaking, your thermostat is stuck, or your coolant level is low, the head gasket takes the hit. Coolant leak, especially if it’s coming from between the engine and transmission or showing up as milky sludge in your oil, is another dead giveaway. And if you see bubbles in your coolant reservoir while the engine is running? That’s exhaust gases sneaking into the cooling system—a classic sign of a blown seal.

Many people think a blown head gasket means you need a whole new engine. That’s not always true. Sometimes, a professional repair or even a high-quality gasket replacement can bring your car back to life. But waiting too long? That’s when you start paying for a new engine instead of just a gasket. The good news? You don’t have to guess. The posts below show you exactly how to spot the symptoms, what tests mechanics use to confirm it, and how to avoid being overcharged for repairs. Whether you’re checking your own car or deciding whether to fix it or walk away, you’ll find real, no-fluff advice here.