Mercedes-Benz M113 (4.3–6.0 V8)

Mercedes-Benz's V8 of the late 1990s and 2000s, including the supercharged M113K of the E55 and CLS55 AMG, which remains one of the most respected engines the company has built. The V6 of the same generation is the M112.

It is a three-valve, single-plug-per-cylinder design, which is the identifying feature and the source of its one systemic complaint: the ignition system works hard, and coil and plug failures produce misfires that are cheap to fix but frequent. The engine itself is durable well past high mileage.

The faults that do arrive are peripheral rather than internal — the crankcase ventilation system, and the harness insulation on the earliest examples, where biodegradable wiring loom material became brittle and caused fault patterns that look electrical because they are. On the supercharged M113K the intercooler pump and the supercharger clutch are the two items that decide whether the car makes its power.

⚑ It is a family, not a size. This catalogue's own rows carry it at 5.0, 5.4, 5.5 and 6.0 litres across six models, and the 4.3 sits beneath them — so a figure quoted for the M113 describes one member. Establish the displacement before ordering anything, because the AMG 5.4 and the ordinary 5.0 share a name and very little else.