Mitsubishi 4N1 (DI-D)

inline-4 · turbocharged · diesel · 2010–present

Also known as: 4n14, 4n15, 2.2 di-d, 2.4 di-d, di-d, 4n13, 4n16

Mitsubishi's common-rail diesel family — the 2.2 in the Outlander and ASX and the 2.4 in the L200 and Pajero Sport, replacing the older 4D5 series.

The recurring complaints are the modern diesel set: EGR valve and cooler blockage, particulate filter regeneration failure, and injector wear — with the underlying cause on most cars being duty cycle rather than any component. These vehicles are frequently used for short journeys or heavy low-speed work, both of which prevent the filter reaching regeneration temperature.

The consequence worth naming is oil dilution: repeated failed regeneration puts fuel into the sump, the level rises and viscosity falls, and bearing damage follows. A rising oil level on a 4N1 is a fault report. On the L200 and Pajero Sport, which do genuine work, the turbocharger's variable-geometry mechanism sticking with carbon is the other frequent finding, and it often frees with cleaning rather than needing replacement.

Cars fitted with this engine

9 generations, across 1 make. From the authored catalogue — an absent car means the catalogue has not reached it, not that the engine was never fitted.

Mitsubishi

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