Mitsubishi 4B40
1.5 L · inline-4 · turbocharged · petrol · 2017–present
Also known as: 4b40, 4b4, 1.5 turbo mitsubishi, eclipse cross engine
Mitsubishi's 1.5 turbo — in the Eclipse Cross and the Outlander.
It is a modern direct-injected turbo four and its faults are that family's: intake-valve carbon is expected at mileage rather than a defect, because no fuel washes over the valves, and it produces a rough idle and a hesitant pull-away that respond to cleaning.
The turbocharger's oil feed is what the service interval is really protecting, and on an engine this small making this much power that is the failure mode rather than routine advice.
In the Outlander it is a mild hybrid, so start, stop and charge complaints there belong to that system rather than to the engine — and the same engine in the Eclipse Cross has none of it.
It is not the 4B1 family that preceded it and shares the number but not the design; mitsubishi-4b1 is a separate page here.
Cars fitted with this engine
2 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.
Information, not instruction
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