Mercedes-Benz E 320 CDI W211 — Reliability
Reliability Summary
Best engine
OM648 — 84/100
BUY
Worst engine
OM642 — 65/100
CAUTION
Average reliability
74/100
Engine Comparison
| Engine | Reliability Score | Verdict |
|---|---|---|
|
OM648
3.2L CDI Diesel I6 |
84/100 | BUY |
|
OM642
3.0L V6 Diesel |
65/100 | CAUTION |
Engines in this model
BUY
84
OM648
3.2L CDI Diesel I6
The 2002-2006 3.2 CDI straight-six in the W211 E 320 CDI and W220 S 320 CDI - successor to the OM613...
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CAUTION
65
OM642
3.0L V6 Diesel
Smooth, strong 3.0 V6 diesel that goes 300,000+ km when maintained - but four expensive weak spots: ...
View details →Known Issues Across All Engines
| Issue | Engine | Severity |
|---|---|---|
| EGR valve fouling (city use) | OM648 | moderate |
| Injector seal leaks (black death) and glow plugs | OM648 | minor |
| Crankshaft main bearing failure (mainly up to MY 2009) | OM642 | critical |
| Valley oil cooler seal failure | OM642 | high |
| Swirl flap / intake port shut-off (EKAS) failure | OM642 | high |
| EGR valve and cooler sooting | OM642 | moderate |
| BlueTEC NOx / emissions software recall | OM642 | moderate |
FAQ
Is the Mercedes-Benz E 320 CDI reliable?
The Mercedes-Benz E 320 CDI has 2 engine options with reliability scores ranging from 65/100 (CAUTION) to 84/100 (BUY). Average reliability: 74/100.
Which Mercedes-Benz E 320 CDI engine is most reliable?
The OM648 is the most reliable engine in the Mercedes-Benz E 320 CDI, scoring 84/100 (BUY).
What problems does the Mercedes-Benz E 320 CDI have?
Across all engine variants, the Mercedes-Benz E 320 CDI has 7 known issues. The most common are related to EGR valve fouling (city use), Injector seal leaks (black death) and glow plugs, Crankshaft main bearing failure (mainly up to MY 2009).