"Is the E Serisi E400d reliable, and what should you check?"
The most commonly reported issue when buying a used Mercedes-Benz E-Class E400d 2021 (213 / 238 / Facelift): AdBlue system / SCR unit failure. Also, abnormal DPF regenerations and AdBlue consumption/integration are frequently reported.
Engine: OM656
OM656D29SCR · diesel · E400d · Used in this car from 2021-2023
Known engine issues
Camtronic variable valve timing issuesMost problems are related to the Camtronic variable valve timing system.
Camtronic actuator replacementWhen it fails, the drive solenoids, controlled camshaft, and rockers are replaced.
Fuel system sensitive to poor dieselDoes not tolerate poor diesel fuel; the CR Bosch CP4 fuel system with piezo injectors is affected.
+2 more issues on the engine detail page
Known issues and risks
Listed from most frequently reported, each with its source.
AdBlue system / SCR unit failure
Often reported
Owners report exhaust after-treatment system (SCR unit / AdBlue dosing) failures; AdBlue system components and urea injectors need replacement
Exhaust Emissions
Abnormal DPF regenerations and AdBlue consumption/integration
Often reported
Some users report higher than expected DPF regeneration frequency and excessive AdBlue consumption, leading to repeated service visits
Exhaust Emissions
NOx sensor failures (risks for DPF/SCR)
Often reported
Failures in NOx sensors can cause warning messages, incorrect AdBlue dosing, and in prolonged cases, clogging of the DPF/SCR system
Exhaust Emissions
Mercedes-Benz E Serisi E400d technical specs
Mercedes-Benz E Serisi E400d (2021): boot 540 L; fuel use 6,4 l/100 km (urban 8,4 l/100 km · extra-urban 5,2 l/100 km); 0–100 in 4.9 s.
Boot capacity
540 L
Fuel consumption
6,4 l/100 km (urban 8,4 l/100 km · extra-urban 5,2 l/100 km)
What should I look for when buying a Mercedes-Benz E-Class E400d?+
When buying a 2021 E400d, check the service history, test drive, and engine/transmission warnings. The most frequently reported issues: AdBlue system / SCR unit failure; abnormal DPF regenerations and AdBlue consumption/integration; NOx sensor failures (risks for DPF/SCR).
What are the chronic problems of the Mercedes-Benz E-Class E400d?+
The most frequently reported issues: AdBlue system / SCR unit failure; abnormal DPF regenerations and AdBlue consumption/integration; NOx sensor failures (risks for DPF/SCR).
Is the Mercedes-Benz E-Class E400d reliable?+
Rather than a simple yes/no, it's best to weigh the proven pros and cons together. This page lists 3 verified findings.
How does Carbeak collect data?+
The cards on this page are derived from the Difetti fault database records; compatibility of brand, fuel, engine, and generation between the source vehicle and target vehicle is verified. Topics with insufficient evidence are not shown.
We only publish claims we can verify. Cards come from Difetti fault records matched to this vehicle on brand, fuel, engine and generation.
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