Toyota 2L / 3L / 5L

Toyota's older diesel four — the 2.4 2L, 2.8 3L and 3.0 5L — in the Hilux, 4Runner and Fortuner.

It is an indirect-injection engine with a mechanical pump, which puts it on the far side of every modern diesel line: no common rail, no particulate filter, no EGR cooler, nothing to regenerate. Almost every modern diesel complaint is inapplicable, and that is most of why these are still working in places where a modern one would not be.

Its known item is the cylinder head, which cracks between the valve seats — a genuine pattern on the 2L and 3L rather than a rumour, and usually the consequence of an overheat. Coolant loss with no external leak is the tell, and a chemical block tester answers it before anything is stripped.

The timing belt drives the injection pump as well as the camshaft, so a belt service is not the job it is on a petrol engine and getting the pump timing back is the part that takes the skill.

Glow plugs and their relay are the commonest cold-start fault and are testable in minutes. The 1KD/2KD D-4D engines that replaced these are common-rail and have their own page here — nothing about the two families transfers.