Mercedes-Benz E 300
Current four-cylinder turbo with 48V mild hybrid and integrated starter-generator (ISG). Higher output than predecessor at lower consumption. Also used as PHEV base (CLE 300e).
Modern four-cylinder cruiser
200 kW from the M254 four-cylinder is enough for brisk driving, but the W213 prioritises comfort. Solid, without excitement.
Engine Weaknesses 6
Early M254 production batches 2021–2023 show elevated oil consumption due to insufficient piston ring sealing. Mercedes repair involves engine reconditioning.
Symptoms: Dropping oil level between services, bluish smoke on cold start, consumption above 0.5 L/1,000 km
The M254 exhibits timing chain rattle at cold start when oil change intervals are missed. Chain tensioner sealing rings can leak and lose tension. Engine damage is possible.
Symptoms: Rattling or clattering from the engine bay at cold start, disappears after warm-up, worsens with extended service intervals
Defective exhaust valves and guides in the M254 lead to misfires and cylinder head damage. Mercedes USA extended the warranty to 15 years/150,000 miles; no official recall in Germany.
Symptoms: Sudden power loss, severe misfires, CEL flashing, rough engine, dangerous misfires at motorway speed
The 48V mild-hybrid system with integrated starter-generator shows malfunctions: start-stop problems, fault messages and in extreme cases 48V battery failure.
Symptoms: Start-stop system deactivated, EQ Boost warning, hybrid system fault memory, starting problems
The M254 runs three separate electric coolant pumps. Pump failures trigger fault codes P0A05, P00B7, and P0C73. Bleeding requires the Mercedes diagnostic tool.
Symptoms: Coolant temperature warning symbols, insufficient coolant flow, irregular engine temperature, fault codes P0A0500/P00B700/P0C7300
Direct injection without port injection leads to carbon deposits after 50,000–70,000 km. Regular walnut blasting recommended.
Symptoms: Hesitation at part throttle, rough idle, slight overconsumption
Vehicle Weaknesses 14
An incorrectly routed gearbox wiring harness allows water ingress with an increased fire risk. Mercedes issued a recall.
Following software updates, the ECU in individual C238 units was permanently damaged. One owner reported a seven-month workshop stay.
A serial design defect: the tension cables in the soft-top headliner fray and snap after approximately 200–300 roof cycles. Mercedes revised the design from May 2020.
The electric parking brake generates fault messages and seizes, particularly in cold weather. Grinding noises when applying indicate worn components.
The soft-top tension cords fray after just a few hundred opening cycles. A design fault that led Mercedes to carry out goodwill repairs.
At higher mileages the electric motors in the roof kinematics or the hydraulic unit can fail. The roof can then no longer open or close fully.
Brake discs on the W213 show juddering after just a few thousand kilometres. Individual cases report renewed juddering after warranty replacement.
Elevated MOT failure rates at suspension mounts. The double wishbone front axle shows wear at bearings and joints.
Infotainment and driver assistance systems are prone to faults. Brake assist and cruise control warning messages appear without cause. Often resolved via software update.
The electric parking brake is prone to corrosion and seizing. Multiple recall actions for the brake system have been documented.
The electric parking brake generates fault messages and seizes, especially in cold weather. Grinding and creaking noises when releasing are common.
The optional Airmatic air suspension is prone to compressor and air bag failures. Replacement requires removal of the rear axle and is expensive.
The rotary push controller on the centre console is mechanically fragile and shows signs of failure after heavy use.
MBUX system freezes or reboots. Bluetooth connections drop, voice control unresponsive. Software updates only fix some issues.