2018 BMW 2 Series Reliability Report

This catch-all category covers many unrelated faults. Coolant leaks from a cracked oil filter housing or from plastic vent and expansion tank hoses come up often, sometimes returning after repair. Panoramic sunroof glass shatters, and the sunroof shade can sag into the cabin. Other reports cite the power trunk closing on an arm, a driver door unlatching at 40 mph, emergency call backup battery warnings, a vinegar smell from the air conditioning, weak driver-assist alerts, and a crash after sudden acceleration.

False warnings lead this category. The "Passenger restraint system malfunction" message appears at startup or at random, and seat belt chimes sound when the seat is empty or the driver is already buckled. Dealers point to the passenger seat sensor mat, with quotes from over $2,000 up to $2,800, and some warnings return after a warranty repair. Mechanical faults appear too: driver belts that will not retract, a rear buckle that will not latch, and a passenger belt that locked and unlocked repeatedly during a crash.

Leaking hoses, reservoir hoses, and water pumps trigger low-coolant warnings, overheating, reduced power, and stalling while driving. Some cars need a second water pump after the first replacement, and one report describes smoke under the hood and inside the cabin. Reported coolant failures range from 49,000 to 105,000 miles. Leaks from oil cooler lines and turbo lines that contaminate the coolant also appear. Several owners say the manufacturer offered no help with the repair.

Stalling and power loss lead this category. Cars shut off at highway speed or when coming to a stop, sometimes showing "Drivetrain malfunction" or "transmission not in park" messages. Diagnoses include a failed fuel pump and fuel rail line, a VANOS fault after a rough cold start, and coolant leaks that cause jerking. A cracked driveshaft flex disc turns up at 22,000 miles. In one crash, the car accelerated from a stop while the drivetrain warning flashed, and the driver suffered a fractured back.

Two failures stand out. The front passenger door opens by itself while the car is moving, at times with no warning until it swings open, and it can happen more than once on the same car. The sunroof glass shatters on its own at speed with a loud bang, leaving shards on top of the shade. The remaining report concerns collision damage from another vehicle, not a defect.

Seat faults range from distracting to dangerous. The passenger seat occupancy sensor fails and triggers restraint system warnings, with one repair quoted at $2,030. Moisture is sometimes blamed even when the cushion shows no sign of it. The driver seat is reported to slide under braking, and in one low-speed reverse crash it collapsed backward, leading to serious neck injuries. The lumbar support can also inflate on its own while driving, with no warning to the driver.

Sudden unintended acceleration appears in two crash reports, one of them while the driver was pulling into a parking space. A cruise control rocker switch can stick, which keeps raising the speed and in one case pushed it past 80 mph. The remaining report involves a run-flat tire blowout on the freeway with severe vibration, pulling, and grinding that ended in a tow.