Ford Essex V6 (3.8)

Ford's 3.8 V6 — in the Taurus, Thunderbird, Windstar, Mustang and the Mercury equivalents.

⚑ Its head gaskets are the reason it has a reputation, and it is one of the clearest cases in this catalogue of a specific, well-documented, era-limited fault. The gasket fails between a coolant passage and a cylinder, and the symptom is coolant loss with no external leak — no puddle, no wet hose, just a level that keeps falling.

A car losing coolant with nothing on the ground is this fault until proved otherwise, and the confirmation is a combustion-gas test at the header tank rather than a pressure test, because the leak only opens under combustion pressure.

Ford revised the gasket during production, so the model year decides whether an example is likely to have had it already — and a great many surviving cars have.

Beyond that the engine is unremarkable and durable: the recurring items are the lower intake manifold gasket, which seeps coolant externally and is often confused with the head gasket, and the ignition coil pack.

The North American Essex is not the British Essex V6 of the Capri and Granada, which is a different engine sharing only the name.