Mercedes Sprinter Turbo

From the naturally aspirated 2.5 D to the 2.2 CDI bi-turbo: how the Sprinter range redefined its turbos generation after generation

The Sprinter is an exclusively diesel range within this scope — no petrol engines whatsoever. This might seem to simplify identification, but the variety of engine families introduced over several decades creates real pitfalls. From the 2.9 D (OM602, fixed geometry, mechanical wastegate) to the 2.7 CDI (OM612, variable geometry) and the 2.2 CDI (OM611, OM646, OM651), each engine generation requires a distinct turbo architecture. Thermal demands differ considerably: OM602 engines run at lower oil pressures and exhaust temperatures than variable-geometry CDI units, where the actuator and moving vanes are directly exposed to hot gases and carbon build-up.

Engine families and turbos: the key pairings you need to know

The OM611 and OM646 cover the majority of 211 CDI, 311 CDI, 411 CDI and their variants, yet they do not share the same turbo despite an identical engine capacity of 2.2 litres. The power suffix (109 hp, 129 hp, 150 hp) and the exact engine code (for example OM 646.984, OM 646.985, OM 646.986, OM 646.989, OM 646.990 or OM 646 DE22LA) are the only reliable references for identifying the correct turbo. The same commercial designation — 313 CDI — can correspond to different engine codes depending on the vehicle's generation, and the associated turbos are not interchangeable.

The Sprinter CDI 2.1 bi-turbo (OM651) is a special case: it uses two turbos in series — a small one at low revs and a large one under high load. Replacing only one of the two without a full diagnostic of both stages is a common mistake. For the 2.7 CDI (OM647, 156 and 170 hp), the variable geometry is sensitive to oil quality and the condition of the lubrication circuit; a seized CHRA or worn bearings typically present as a whistling noise under acceleration and a gradual loss of power before full limp-home mode sets in. Whatever the generation, diagnosing the root cause of the failure — degraded oil, carbon fouling, foreign body in the intake — is essential before any replacement.

New and reconditioned turbos: what this collection offers

The vast majority of references available here are new turbos, sold as a straightforward purchase with no unit to return. One specific reference for the 2.2 CDI (129 hp / 150 hp, codes OM 646 DE22LA) is available in a reconditioned version. OEM and equivalent references cover a wide spectrum: VV17, 709836, 709838, 759688, 761154, 823631 and their Mercedes equivalents (prefixes A646…, A612…, A642…, A611…, A647…) are all listed in the catalogue. Always check the engine code stamped on the block before placing an order — it is the only way to avoid a reference error across such a fragmented range.