BMW 116d
Modular three-cylinder diesel in the entry-level trim. Adequate for city use but marginal on the motorway. Few known issues thanks to low production numbers.
Three-Cylinder Diesel
BMW's smallest diesel — noticeably underpowered in an SUV or van.
Engine Weaknesses 7
The B37D15 shares design features with the N47 and can develop a stretched timing chain with skipped oil changes or short-trip use. Immediate diagnosis at the first rattle is advisable.
Symptoms: Metallic rattling on cold start (loudest when cold), noise subsides after reaching operating temperature, engine warning light, rough running in advanced stages.
The small 3-cylinder diesel rarely reaches the exhaust temperature needed for DPF regeneration on short trips. Particulate filter clogs up.
Symptoms: DPF warning light, power loss, increased fuel consumption, limp mode
The common-rail injectors of the B37D15 wear above average with frequent short-trip use. Incomplete DPF regeneration cycles cause fuel dilution of engine oil, putting additional strain on the injectors.
Symptoms: Stumbling and misfires, difficult cold starting, increased consumption, engine warning light.
Aborted DPF regenerations caused by short-trip driving are a problem on the B37D15: fuel enters the engine oil, diluting it and damaging bearings and injectors. Regular motorway driving is necessary.
Symptoms: Oil level rises (fuel in oil), decreasing engine oil viscosity, engine warning light, DPF full message.
Glow plugs seize in their threads and snap during removal — a well-known problem on modern BMW diesel engines. A broken glow plug in the cylinder head requires time-consuming extraction.
Symptoms: No direct driving symptoms before breakage. The symptom is the breakage during a service visit — cold-start difficulty points to worn glow plugs.
Frequent urban and short-trip use causes soot deposits in the EGR valve of the three-cylinder diesel. A sticky valve disrupts EGR control and leads to power loss.
Symptoms: Stumbling and poor throttle response on cold start, engine warning light, increased emissions, higher fuel consumption in urban driving.
Moderate oil consumption of about 1 L/20,000 km is normal for this 3-cylinder. BMW quotes up to 0.7 L/1,000 km as acceptable.
Symptoms: Occasional top-up required, oil level warning between service intervals
Vehicle Weaknesses 6
EPS issues are widespread on the F20: the rack binds, aluminium bolts corrode on vehicles built July 2011–May 2015, and the electric motor can detach from the rack. Full replacement usually necessary.
The EGR valve and EGR cooler can fail or leak on N47 and B47 diesel engines. In the worst case, coolant ingress can cause engine fire.
Water enters through displaced cable grommets, faulty door seals, or blocked sunroof drains. Problem occurs across all F20 production years.
On N13 and N55 engines, valve cover gaskets go brittle and the crankcase ventilation fails. Oil consumption rises to 0.5–1 litre per 3,000 km.
Shaft seals on the rear differential leak gear oil. Problem often appears as early as 25,000–50,000 km, especially on M135i and M140i.
Clattering rear axle caused by worn shock absorbers, known from production date 04/2012 onward. Dampers are regularly flagged at MOT. Track rod ends also wear prematurely.
Reports & Tests
160 owner complaints filed with NHTSA (2011–2019). Most reported: Airbags (85), Engine (24), Engine & Cooling (20).