Mercedes OM646 2.2 CDI Engine: Specs, Reliability & Failure Analysis
The Mercedes-Benz OM646 is a 2.2-liter inline-four common-rail diesel engine family used in both passenger-car and commercial-vehicle applications. The family designation covers multiple engine suffixes, output calibrations, emissions configurations and vehicle-specific installations, so specifications and known issues cannot safely be treated as universal across every OM646-equipped vehicle. The most clearly documented passenger-car version is OM646.811,…