Ford Zetec (badge, not an engine)

Zetec is a badge, not an engine — and by the end of its life it was not even an engine badge, but a trim level.

Ford introduced it in 1991 for a sixteen-valve petrol four, applied it to at least three unrelated families — the original Zeta, the Zetec-SE which became the Sigma, and the Zetec-E — and then moved the word onto the boot lid of cars whose engines were called something else entirely. A modern Fiesta Zetec has a Duratec or an EcoBoost under the bonnet.

So the badge on the back tells you almost nothing about the engine, and this is the clearest case in the catalogue of a name outliving the thing it named. Establish the displacement and the family — the Sigma, the Duratec, the EcoBoost — all of which have pages here.

Where it does still name an engine, it names a naturally aspirated sixteen-valve petrol four, and the recurring items on those are ordinary: the coil pack, the idle air control valve on the earlier ones, and a cam belt whose interval is real because the engines are of an era when belts were the norm.