Toyota 5S-FE

Toyota's 2.2-litre four of the 1990s — the Camry, Celica, MR2, Solara and the first-generation RX 300's platform siblings. It has a reputation for lasting more or less indefinitely and it is deserved, which changes what a fault on one means: an engine of this family running badly is very rarely worn out.

It is a non-interference design, and that is the single most useful thing to know about it. The timing belt drives the camshafts, and if it breaks the pistons do not meet the valves. A snapped belt on this engine strands the car and does not destroy it — which is the opposite of most of its contemporaries, and it changes the calculation on a cheap example with no belt history entirely.

What actually goes wrong is peripheral. Oil leaks are the commonest complaint — the valve cover gasket, the distributor O-ring and the oil pump seal all harden with age, and oil arriving at the distributor produces misfires that read as ignition faults because they are. The knock sensor and its harness fail at mileage and set a code without any audible symptom, and the front crankshaft seal weeps.

Oil consumption climbs late in life. On an engine this durable that is wear rather than a defect, and topping up is a reasonable answer where it would not be on a younger engine.