"Is the 4 Serisi 418i reliable, and what should you check?"
The most frequently mentioned issue when buying a used BMW 4 Series 418i 2017 (F32 / F33 / F36 / F82 / F83): Cooling system: pump and thermostat. Also, timing chain tensioner and chain are commonly reported.
Engine: B38
B38B15A · 418i · Used in this car from 2017-2019
Known engine issues
Crankshaft thrust bearingEngines up to 2015 suffered from excessive axial clearance on the crankshaft, and the thrust bearing failed at 50,000 km. The design was later revised.
Cracks in the manifoldThe aluminum turbocharger housing with water cooling is integrated with the exhaust manifold and cracks from overheating, leading to coolant leakage.
Floating idleAs with all direct injection engines, intake valves become coked with carbon deposits, resulting in floating idle and unstable engine operation.
+1 more issues on the engine detail page
Known issues and risks
Listed from most frequently reported, each with its source.
Cooling system: pump and thermostat
Often reported
Issues in the cooling circuit, including thermostat and water pump anomalies, are reported that can cause engine temperature fluctuations or risk of overheating. If not detected in time, these faults can lead to major engine damage.
Cooling
Timing chain tensioner and chain
Often reported
In some variants of the 1.5 engine (B38), timing chain stretch and tensioner wear are reported; this can cause a rubbing or rattling noise on cold start and, if neglected, carries a risk of serious mechanical damage.
Timing chain
Injectors and carbon buildup
Often reported
Injector failures and carbon deposit formation on intake ports are reported; this can cause idle fluctuation, loss of efficiency, and higher fuel consumption.
Fuel System
Turbocharger issues (wastegate/oil)
Often reported
In many 1.5 versions, the turbocharger may experience wastegate failures or performance loss due to clogged oil passages or faulty actuators.
Turbo
BMW 4 Serisi 418i technical specs
BMW 4 Serisi 418i (2017): boot 445 L; fuel use 5,6 l/100 km (urban 7,1 l/100 km · extra-urban 4,8 l/100 km); 0–100 in 9 s.
Boot capacity
445 L
Fuel consumption
5,6 l/100 km (urban 7,1 l/100 km · extra-urban 4,8 l/100 km)
What should I look for when buying a BMW 4 Series 418i?+
When buying a 2017 418i, check the service history, perform a test drive, and look for engine/transmission warnings. Most commonly reported issues: Cooling system: pump and thermostat; Timing chain tensioner and chain; Injectors and carbon buildup.
What are the common problems of the BMW 4 Series 418i?+
Most frequently reported issues: Cooling system: pump and thermostat; Timing chain tensioner and chain; Injectors and carbon buildup.
Is the BMW 4 Series 418i reliable?+
Rather than a simple yes/no, it's best to weigh the proven pros and cons together. This page lists 4 verified findings.
How does Carbeak collect data?+
The cards on this page are derived from Difetti fault database records; brand, fuel, engine, and generation compatibility between the source vehicle and target vehicle are verified. Topics with insufficient evidence are not shown.