Mercedes-Benz E 250 D
Five-cylinder with swirl-chamber injection, also as turbodiesel. Robust design with good mileage potential. Check turbocharger on TD version.
Underpowered
Just 83 kW — barely enough to keep up with traffic.
Engine Weaknesses 7
The 4-valve cylinder head shows increased valve guide clearance at high mileage. Oversize boring requires special tooling; seal kits are no longer regularly available.
Symptoms: Blue smoke on acceleration or after overrun, increased oil consumption, slight ticking from valvetrain
Porous O-rings on the solenoid shut-off valve and defective non-return valves allow fuel to drain back to the tank. After prolonged standing, the system has to be laboriously refilled.
Symptoms: Engine will not start after several days standing, fuel lines to filter empty, long cranking required
The turbocharger on the OM605 (605.960/961) is prone to shaft seal leaks. Engine oil enters the intake system and burns with blue smoke.
Symptoms: Blue smoke from exhaust especially when accelerating after idle, oil in intake pipe, increased oil consumption, power loss
On the OM605, head gasket failure is less common than on the OM602, but fatigue cracks increase from approximately 300,000–400,000 km. The pre-chamber head is sensitive to uneven heat distribution.
Symptoms: Coolant loss, oil film in expansion tank, hydraulic tappet noise at cold start, white vapour from exhaust
Like the OM604 and OM606, the OM605 shares the intake valve stem elongation issue. Special BGA repair tappets (1 mm shorter, approximately €10 each) allow a cost-effective repair.
Symptoms: Difficult cold starting, engine requires multiple attempts in cold weather, rough running until operating temperature, quiet ticking in valve area
The OM605 turbodiesel is heavier than the naturally aspirated version and loads the engine mounts more. After replacing all three mounts the engine runs like new.
Symptoms: Vibrations at idle and low revs, engine visibly rocking, judder when pulling away
The alternator shows regulator and brush problems at high mileage. Regulator replacement approximately €49 (Bosch), complete alternator €100–€200 (aftermarket).
Symptoms: Battery warning light, battery not being charged, voltage drop with high electrical loads
Vehicle Weaknesses 6
Bacterial contamination in the electrophoretic coating bath compromised paint adhesion. Rust appears on doors, roof, boot lid and trim strips. Mercedes offered goodwill repairs.
Strut towers corrode severely and can break away from the bodywork. Safety-critical defect: the vehicle can drop uncontrollably.
Wheel arches, sills and strut towers rust heavily. Hidden rust forms beneath the sill cladding.
Front and rear strut towers rust through. At the front the towers can break while driving. At the rear this is an economic write-off.
Electronic ignition lock wears out over time. Key turns but vehicle won't start. Problems worsen in cold weather.
Typical electrical problems: alarm system triggers false alerts, cruise control cuts out, air conditioning shows faults. Cable oxidation is frequently the cause.