BMW 114d

Same timing chain issue as the larger N47D20. The chain is gearbox-side mounted and the tensioner can fail. Replacement is labour-intensive.

Symptoms: Rattling on cold start, engine warning light, rough idle

Like all N47 derivatives, the N47D16 shares the notorious timing chain issue. Plastic guide rails wear prematurely; the rear-mounted timing chain requires engine removal for repair.

Symptoms: Rattling on cold start (from the rear of the engine), engine warning light, in the worst case sudden engine failure.

A leaking EGR cooler allows glycol into the intake system — in combination with soot deposits and high temperatures, glowing particles can form and create a fire risk. Affects build years 2010–2017.

Symptoms: Power loss, sweet coolant smell from the engine bay, engine warning light, in severe cases visible smoke from the engine bay.

Plastic swirl flaps in the intake manifold can break off with age and be ingested into the combustion chamber — piston and cylinder head damage follows. BMW fitted metal swirl flaps in later build years.

Symptoms: No direct warning — in extreme cases sudden engine power loss, metallic noises, or complete engine shutdown.

Injectors corrode in the cylinder head and can no longer be removed easily. Forced extraction with special tools can damage the cylinder head — significant additional costs result.

Symptoms: No prior driving symptoms — problem emerges during a workshop visit. Prior signs: smoking, rough running, poor cold-start behaviour.

The N47D16 in the 116d is prone to DPF clogging with predominantly short-trip use, as regeneration cycles are terminated too early. Complete DPF blockage requires costly cleaning or replacement.

Symptoms: DPF warning display, power loss, limp mode, frequent ECU regeneration attempts.

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.