Fuel Filter Replacement — OM646 (2.1L CDI)

NCV3 Sprinter (2007–2018) · 2.1L 4-cylinder OM646 / OM651

Replace the engine-mounted spin-on fuel filter on the OM646 four-cylinder NCV3 Sprinter. Different housing, different procedure, and a different prime sequence than the OM642 V6 — get it wrong and the high-pressure pump can pull air and fail to start.