Here's why:
* Overheating: A blown head gasket allows coolant to leak into the combustion chambers. This leads to overheating because the cooling system is losing its coolant.
* Smoke from air intake: Coolant entering the combustion chambers turns to steam. This steam is forced out through the engine's exhaust system, but some can also be pushed back into the intake manifold, leading to white or whitish-grey smoke from the air intake.
While the radiator and thermostat are ruled out, other possibilities (though less likely given the symptoms) include:
* Cracked engine block or cylinder head: This would also allow coolant to leak into the combustion chambers, resulting in similar symptoms. However, a head gasket failure is far more common.
* Clogged cooling passages within the engine: Less likely to cause smoke from the intake, but could contribute to overheating. This would usually manifest as gradual overheating without the smoky symptom.
It's crucial to get this diagnosed and repaired immediately. Driving the vehicle with a blown head gasket will cause significant engine damage, potentially requiring a costly engine rebuild or replacement. A mechanic can perform a pressure test on the cooling system and a compression test on the cylinders to definitively diagnose a head gasket failure.
