Injector copper seals ('black death')
usually 100,000–250,000 km · High risk
Signs: Ticking, soot around injectors, diesel smell in the cabin
Fix: Replace seals and hold-down bolts early
€200–1,200
Engine: common problems, timing drive and oil
2.2 CDI (Mercedes OM646)
Diesel · 2,148 cm³ · 65–125 kW
7
model generations
4
known faults
215,000
new cars in the EU (2010–2025)
Enter your VIN and mileage and get a plan built for your exact engine and gearbox.
Fuel: Diesel. Timing drive: chain.
In our database this engine is fitted to 7 model generations, among them: Mercedes-Benz C-Class (W204), Mercedes-Benz GLK (X204), Mercedes-Benz Vito (W639), Mercedes-Benz Sprinter (906), Mercedes-Benz C-Class (W203), Mercedes-Benz E-Class (W211) and 1 more.
The most expensive known risk is injector copper seals ('black death'): it usually appears at 100,000–250,000 km and costs €200–1,200 to fix.
Key facts
| Fuel | Diesel |
|---|---|
| Displacement | 2,148 cm³ |
| Power | 65–125 kW |
| Years | 2002–2010 |
| Timing drive | Chain |
| Oil | 5W-30 / 5W-40 · MB 229.31 / 229.51 · ~6.5 L · every 15,000 km |
| Engine codes | OM646 |
Known engine faults
Faults that belong to the engine itself. They apply to every model with this engine, and each model has its own extra faults on its model page.
Glow plugs seized
usually 150,000–250,000 km · Medium risk
Signs: Hard cold start; plugs snap on removal
Fix: Replace with care
€200–900
Oil cooler / filter housing seals
usually 150,000–250,000 km · Medium risk
Signs: Oil leak down the block
Fix: Reseal
€300–700
EGR / swirl flap actuator
usually 120,000–220,000 km · Medium risk
Signs: Limp mode
Fix: Clean or replace
€300–900
Engine-related service
Intervals and typical prices, using the Mercedes-Benz C-Class (W204) as an example. The app gives the exact plan for your car.
| Item | Interval | Typical price |
|---|---|---|
| DPF health check (soot / ash load)Emissions | every 20,000 km | €0–60 |
| Engine oil + oil filterEngine | every 15,000 km or every 12 months | €70–150 |
| Air filterEngine | every 30,000 km or every 24 months | €15–45 |
| Fuel filterFuel | every 30,000 km or every 24 months | €40–110 |
| Glow plugsEngine | every 100,000 km | €120–300 |
| Auxiliary (serpentine) beltEngine | every 120,000 km | €70–180 |
| Coolant replacementCooling | every 150,000 km or every 96 months | €70–150 |
| Timing chain inspection (listen on cold start)Engine | every 150,000 km | €0–120 |
Models with this engine
Model generations this engine is fitted to.
Mercedes-Benz C-Class (W203) 2000–2007Mercedes-Benz C-Class (W204) 2007–2014Mercedes-Benz CLK (C209) 2002–2010Mercedes-Benz E-Class (W211) 2002–2009Mercedes-Benz GLK (X204) 2008–2015Mercedes-Benz Sprinter (906) 2006–2018Mercedes-Benz Vito (W639) 2003–2014
Common questions
Does the 2.2 CDI (Mercedes OM646) engine have a timing chain or a timing belt?
Chain.
What oil does the 2.2 CDI (Mercedes OM646) engine take?
5W-30 / 5W-40 · MB 229.31 / 229.51 · ~6.5 L · every 15,000 km.
What are the known problems with the 2.2 CDI (Mercedes OM646) engine?
The faults with the highest risk: injector copper seals ('black death') (100,000–250,000 km, €200–1,200); glow plugs seized (150,000–250,000 km, €200–900); EGR / swirl flap actuator (120,000–220,000 km, €300–900); oil cooler / filter housing seals (150,000–250,000 km, €300–700).
Which cars have the 2.2 CDI (Mercedes OM646) engine?
Mercedes-Benz C-Class (W204), Mercedes-Benz GLK (X204), Mercedes-Benz Vito (W639), Mercedes-Benz Sprinter (906), Mercedes-Benz C-Class (W203), Mercedes-Benz E-Class (W211) and 1 more.
Sources and notes
Faults, intervals and prices are indicative and collected from public sources and owner experience; always rely on the service book and a qualified workshop. Test statistics: DVSA – Anonymised MOT tests and results, Open Government Licence v3.0. Dutch tests: RDW Open Data (CC0). Engine versions: EEA, monitoring of CO₂ emissions from new passenger cars (CC BY 4.0, DG CLIMA). Owner complaints: NHTSA ODI (public domain). Recalls: DVSA Vehicle Safety Branch Recalls Database, OGL v3.0. Brand and model names are trademarks of their owners and are used only to describe the vehicles.
Updated 08/10/2026