Buy a high-quality PDF from a reputable source like Tradebit or download the Mercedes WIS (Virtual Machine) setup from a trusted torrent (legality varies by country—buy used DVDs legally).
: Haynes provides practical, step-by-step rebuild guides based on complete vehicle teardowns. Note that later Sprinter manuals (July 2009 onwards) typically cover the OM651 engine, so ensure you select the manual for the pre-July 2009 models for OM646 coverage. Mercedes Workshop Manual Om646 Engine
(common-rail direct injection), electrical equipment, and cooling systems. Maintenance Schedules: Buy a high-quality PDF from a reputable source
Located at the top-center of the engine. Requires pliers for click-style hose clamps. Ensure the ignition is cycled several times to prime the low-pressure pump before starting. Mercedes Workshop Manual Om646 Engine