"Is the 6 Serisi 640i reliable, and what should you check?"
When buying a used BMW 6 Series 640i 2011 (F06 / F12 / F13), the most commonly mentioned issue is oil leaks from gaskets and the valve cover. Carbon buildup on valves and injectors, as well as a tendency to fail, are also frequently reported.
Engine: N55
N55B30A · 640i · Used in this car from 2011-2018
Strengths
Engine is widely used
Good potential for chip tuning
Watch-outs
Frequent vacuum leaks
Oil and coolant leaks
Some parts are very expensive
Known engine issues
Injectors and High-Pressure Fuel PumpEarly production engines used a short-lived HPFP from the predecessor, causing many issues. A more reliable pump appeared only in March 2012. Injectors were electromagnetic from the start and have no particular problems.
TurbochargersThe BorgWarner turbo lasts long with regular quality maintenance. Main owner complaints are about rapid wastegate valve wear and actuator failure (both versions).
Timing ChainThe chain itself has decent life, stretching after 200,000 km. However, its plastic guides are very sensitive to overheating and can crack. Engines before 2012 often had bolts shearing on VANOS units.
Listed from most frequently reported, each with its source.
Oil leaks from gaskets and valve cover
Often reported
Many users report oil leaks from the valve cover and oil filter housing gaskets. These leaks typically appear with age or high mileage and may occasionally cause smoke, residue, and oil smell.
Engine Bay
Carbon buildup on valves and injectors, tendency to fail
Often reported
Carbon buildup on intake valves is common in direct injection engines over time, causing sluggishness, idle fluctuation, and reduced performance. Some injectors and fuel system components are reported to be prone to failure.
Engine Internal
Cracked or weakened charge pipes/plastic components
Often reported
Turbocharger charge air pipes and fittings made of plastic/polycarbonate may crack or break over time, causing pressure loss, sudden power loss, or triggering the check engine light.
Turbo
Turbo / Wastegate Issues
Often reported
Turbocharger failures are reported, including abnormal noises (rattling), wastegate malfunctions, and oil contamination or reduced mechanical sealing due to thermal stress or inadequate maintenance. These faults lead to performance loss.
Turbo
BMW 6 Serisi 640i technical specs
BMW 6 Serisi 640i (2011): boot 460 L; fuel use 7,8 l/100 km (urban 10,5 l/100 km · extra-urban 6,2 l/100 km); 0–100 in 5.4 s.
Boot capacity
460 L
Fuel consumption
7,8 l/100 km (urban 10,5 l/100 km · extra-urban 6,2 l/100 km)
What should I look for when buying a BMW 6 Series 640i?+
When buying a 2011 640i, check the service history, perform a test drive, and look for engine/transmission warnings. The most commonly reported issues are: oil leaks from gaskets and the valve cover; carbon buildup on valves and injectors with a tendency to fail; and cracked or weakened charge pipes/plastic components.
What are the common problems of the BMW 6 Series 640i?+
The most frequently reported issues are: oil leaks from gaskets and the valve cover; carbon buildup on valves and injectors with a tendency to fail; and cracked or weakened charge pipes/plastic components.
Is the BMW 6 Series 640i reliable?+
Rather than a simple yes or 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 the Difetti fault database records; the source vehicle is verified for brand, fuel type, engine, and generation compatibility with the target vehicle. Topics with insufficient evidence are not shown.