Vehicles using OM642.920 engine list:

Engine OM642.920

Symptoms:
- Rough idling and loss of power
- Excessive smoke from the exhaust, particularly black or blue smoke
- Engine warning light or diesel particulate filter (DPF) warning illumination
- Increased fuel consumption
- Hard starting or misfires

Diagnosis:
- Check for clogged or malfunctioning diesel particulate filter (DPF), common in these models due to soot buildup
- Inspect turbocharger for wear or failure, as turbo issues are frequent in OM642 engines
- Test fuel injectors for leaks or poor spray pattern causing misfires or rough running
- Examine EGR (Exhaust Gas Recirculation) valve for carbon deposits leading to blockage and poor emissions control
- Scan for fault codes related to sensors such as MAF (Mass Air Flow), MAP (Manifold Absolute Pressure), or crankshaft position sensor

Fixes:
- Perform DPF regeneration or replacement if clogged beyond cleaning
- Replace or repair faulty turbocharger components, including actuator and bearings
- Clean or replace fuel injectors to restore proper combustion
- Clean or replace EGR valve to ensure correct exhaust gas recirculation
- Replace faulty sensors and clear engine fault codes after repairs
- Regular oil and filter changes with manufacturer-specified fluids to prevent premature wear

Prevention:
- Use high-quality diesel fuel and adhere to recommended oil change intervals to reduce deposits
- Avoid frequent short trips that prevent DPF regeneration; allow engine to reach operating temperature regularly
- Periodically inspect and clean EGR and intake systems to prevent carbon buildup
- Monitor turbocharger performance and address unusual noises or power loss early
- Follow Mercedes-Benz service schedules strictly for these models to maintain engine health and emissions compliance