Daihatsu EJ-VE (and the JC-DET, 0.7 and 1.0)

Daihatsu's 1.0 three-cylinder — in the Mira, Sirion, Xenia and, badged Toyota, the Passo and first Aygo's cousins.

A three-cylinder is not inherently balanced, and on an engine this small the consequence is very audible: it vibrates and drones at idle as a matter of design. An owner reporting shake at a stop is usually describing normal behaviour, and establishing that first saves chasing mounts.

It is chain-driven and simple, and the EJ-VE adds variable valve timing whose behaviour depends on oil pressure and cleanliness — a flat top end on a neglected one is an oil question first.

Its complaints are the small-engine set: a carboned throttle body giving a hunting idle, ignition coils, and a coolant temperature sensor that ruins economy without setting anything anybody notices. Documentation outside Japan and South-East Asia is thin.