BMW 750i

The timing chain system remains the weak link in the TU as well. Plastic guide rails degrade. Preventive replacement from 120,000–150,000 km is advisable. Repair requires complete engine removal (~40 labour hours).

Symptoms: Rattling on cold start, engine warning light, in extreme cases loud clattering and engine failure

Despite revision, valve stem seals can wear at high mileage. Oil consumption of 0.5–1 L/5,000 km is reported by TU owners. Significantly better than the original N63, but not fully eliminated.

Symptoms: Slightly elevated oil consumption, occasional light blue smoke on cold start, oil level warning earlier than expected

Hot-V design remains structurally prone to oil carbon build-up in the turbo feed lines. Switching the engine off immediately after hard driving promotes deposits and premature turbo wear.

Symptoms: Power loss under load, occasional hissing or whining from the engine bay, rarely blue smoke after a motorway run

Coolant hoses and bleed lines around the turbochargers suffer from sustained heat. Cracks often develop under load and only leak at operating temperature, making diagnosis difficult.

Symptoms: Periodic coolant warning light, loss without visible puddle, occasional coolant smell after shutdown

Wiring harness problems or CAN bus faults cause fault messages across many control units simultaneously.

The PHEV system has no alternator. A fault in the SME module opens the contactors and the 12V battery discharges while driving.

Air bellows become porous from around 100,000–150,000 km; the compressor overheats from frequent pumping and fails. Car sags on one side or completely.

Signal fault in the motor position sensor can deactivate hydraulic brake assist. Approximately 1 million vehicles worldwide.

Recall KBA 16187R: a potentially misrouted cockpit wiring harness can be damaged during cabin filter replacement. A short circuit can cause smoke or fire — 337,374 vehicles worldwide affected.

G11 sags unevenly at all four wheels overnight. No fault code stored.

NOx sensor upstream of the SCR catalyst fails. Complete tank replacement costs 2,500–3,000 €.

Blocked or porous panoramic roof drain tubes channel water into the cabin instead of outside. Water collects in the headlining and runs toward the battery or control units.

Driver assistance systems on the G11 (lane keep assist, blind spot warning, junction assistant) malfunction frequently and require software updates or camera reinitialisations.

Faulty comfort access system draws continuously elevated current and drains the battery.

The interior door opening button integrated into the diamond light strip fails and no longer illuminates. Climate controls on the same side can also fail simultaneously. BMW replaces the entire light strip — approximately 4 weeks lead time.