"Is the 4 Serisi 425d reliable, and what should you check?"
When buying a used BMW 4 Series 425d 2017 (F32 / F33 / F36 / F82 / F83), the most frequently mentioned issue is: oil cooler / oil cooling component failures. Also, EGR / swirl valve clogging (carbon buildup in intake ports) is commonly reported.
Engine: B47
B47D20B · 425d · Used in this car from 2017-2017
Known engine issues
EGR valveMost problems of this engine are related to the EGR system, called AGR here. In early years, the valve could clog at 30,000 km and a recall campaign was even conducted. When it sticks open, overheating causes the intake manifold to crack.
Intake cloggingThe second most frequent service issue is clogging of the intake manifold and ports in the cylinder head, leading to loss of power and unstable engine operation. In severe cases, the intake swirl flaps may stick and break off.
Timing chain stretchThe chain timing drive on B-series engines differs little from N-series predecessors and may require attention before 200,000 km under very active use. There is already a cost-effective procedure to replace these chains without removing the engine.
+1 more issues on the engine detail page
Known issues and risks
Listed from most frequently reported, each with its source.
Oil cooler / oil cooling component failures
Often reported
Owners report breakage or leakage of the oil cooler and oil cooling circuit components; this can render the vehicle unusable and cause difficulty in finding spare parts.
Cooling
EGR / swirl valve clogging (carbon buildup in intake ports)
Often reported
Carbon buildup is reported in EGR valves and swirl flaps on modern N47 diesel engines; this can cause idle fluctuation and performance loss, requiring cleaning or removal.
Engine Bay
Worn timing chain
Often reported
On N47 engines (including 2.0 218 HP), the timing chain and guides frequently stretch and wear; this can cause rattling noises from the engine, electronic warnings, or loss of synchronization. Repair is labor-intensive.
Timing chain
DPF clogging or issues
Often reported
Diesel particulate filter (DPF) and regeneration cycles can cause problems, especially with city or short-distance driving; incomplete regenerations, warning lights, and need for cleaning or replacement may occur.
Exhaust Emissions
Turbo/actuator failures (VGT/wastegate)
Often reported
User reports and technical reports indicate faults or malfunctions in turbocharger components (wastegate actuator or variable geometry) on BMW 2.0 liter diesel engines.
Turbo
BMW 4 Serisi 425d technical specs
BMW 4 Serisi 425d (2017): boot 370 L; fuel use 4,1 l/100 km (urban 5,9 l/100 km · extra-urban 4,7 l/100 km); 0–100 in 6.7 s.
Boot capacity
370 L
Fuel consumption
4,1 l/100 km (urban 5,9 l/100 km · extra-urban 4,7 l/100 km)
What should I look for when buying a BMW 4 Series 425d?+
When buying a 2017 model 425d, check the service history, test drive, and look for engine/transmission warnings. The most commonly reported issues: oil cooler / oil cooling component failures; EGR / swirl valve clogging (carbon buildup in intake ports); worn timing chain.
What are the chronic problems of the BMW 4 Series 425d?+
The most commonly reported issues: oil cooler / oil cooling component failures; EGR / swirl valve clogging (carbon buildup in intake ports); worn timing chain.
Is the BMW 4 Series 425d reliable?+
Rather than a simple yes/no, it's necessary to evaluate the proven pros and cons together. This page lists 5 verified findings.
How does Carbeak collect data?+
The cards on this page are derived from 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.