Mazda SkyActiv-D (S5 / SH / T3)

Inline · twin-turbo · diesel · 2012–present

Also known as: skyactiv-d, 2.2 skyactiv-d, sh-vpts, 1.5 skyactiv-d, s5-dpts, t3-vpts, 3.3 skyactiv-d, skyactiv-d straight-six, s8-dpts

Mazda's SkyActiv diesel, and the mirror image of the petrol engine's approach: where SkyActiv-G raised compression, SkyActiv-D lowered it to about 14:1 — unusually low for a diesel — which allowed the engine to meet emissions limits without selective catalytic reduction on many markets.

That design choice creates its characteristic problem. Low compression makes cold starting and cold running harder, and in short-journey use the result is carbon accumulation in the intake, on the valves and in the EGR circuit, together with oil dilution from repeated regeneration attempts. A 2.2 SkyActiv-D used for city work is the classic case, and the presentation is a cluster of apparently unrelated codes at once.

A rising oil level on one of these is a fault report. Some engines also had issues with the variable-valve-lift mechanism used to aid warm-up. Duty cycle is genuinely the diagnosis here more often than any component is.

The 3.3 straight-six of the CX-60, CX-70 and CX-90 is a different engine and not a bigger 2.2. It is longitudinal, mild-hybrid, and runs a different combustion strategy, so its long-term pattern is not yet established — which is worth saying rather than assuming it inherited the four-cylinder's. The S5, SH and T3 prefixes are what separate the three; the badge on the car does not.

Cars fitted with this engine

10 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.

Mazda

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