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Frequently asked questions about cars and motorcycles

What are the Symptoms of a Blown Head Gasket?

Model: (Various brands) Various
Part: Engine

If your car shows a combination of these four signs, it's time to worry: thick white smoke from the exhaust caused by coolant entering the cylinders and being burned along with the fuel. Then, the engine temperature continuously rises: this happens because exhaust gases (which are extremely hot) enter the cooling circuit, causing the coolant to boil; this occurs even if the coolant level remains normal. If you notice that the coolant level mysteriously drops but see no leaks under the car, the reason is that the coolant is being burned in the engine or evaporated due to excessive pressure in the circuit. Then there’s the classic 'mayonnaise' under the oil cap. When you open the cap, you find a dense beige foam like cream: the result of engine oil mixing with water (but this symptom must accompany one of the others). If the engine struggles to start in the morning, there may be coolant pooling in the cylinders, creating abnormal resistance. If you're on the road and see the temperature skyrocketing, turn the heating on full; this will dissipate excess heat through the internal heater circuit, allowing you to reach a garage.

Posted on 19 September 2026 by ScegliAuto

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