Nissan PR25DD (PR family, 2.0 and 2.5)

Nissan's 2.5 four — in the Altima and, through the alliance, in the Mitsubishi Outlander.

It replaced the long-running QR25DE and is a different engine rather than a development of it: direct injection, a higher compression ratio, and a mirror-bore cylinder coating in place of liners.

⚑ That coating is the thing to know before any machining decision. The bores are plasma-sprayed rather than lined, so a conventional rebore is not available — an engine with bore damage is a different economic question from one with liners.

It is direct-injected, so intake-valve carbon accumulates with mileage because no fuel washes over them, and a rough idle or a misfire at mileage is a cleaning question before it is anything else.

Its appearance in a Mitsubishi is the alliance rather than a coincidence, and Nissan documentation is what applies — which is worth knowing, because searching the Outlander finds very little.

It is too new for a settled long-term record.