2014-2021 Infiniti Q50 Problems: 11 Known Issues

The Q50's 2.0t uses the Mercedes-Benz M274 turbocharged four, shared with the C300 and GLC300. The timing chain and the camshaft adjusters (variable valve timing phasers) wear faster than the engine's design life, with problems commonly surfacing somewhere around 80,000 miles and reported as early as 60,000 on neglected cars. The first symptom is a brief metallic rattle on cold start as oil pressure builds and the tensioner takes up slack. Left alone, chain stretch throws off cam timing, sets correlation codes, and in the worst cases the chain skips teeth or breaks, which on this interference engine destroys valves and pistons. Extended oil change intervals and low oil level accelerate the wear.

On certain 2021 Q50 and Q60 models the Engine Control Module misreads a rapid acceleration event and responds by incorrectly reducing engine power and cutting fuel supply. The driver experiences an abrupt loss of power, and the fuel cut can be severe enough to stall the engine outright — a dangerous failure mode during exactly the maneuvers where full power was requested, such as merging or overtaking. NHTSA campaign 21V234000 covers the defect; Infiniti's internal number is R20C5 and the recall began May 25, 2021.

Early-production VR30DDTT engines leave the factory with the A/C compressor pulley bracket slightly out of plane with the rest of the accessory drive. The misalignment makes the serpentine belt track toward the edge of the smooth idler pulley, where it frays, walks off, and eventually shreds. Because a single belt drives the water pump, alternator, and A/C compressor, losing it means immediate charging failure and rapid overheating, and the shredded belt can damage the pulleys, alternator, and water pump on its way out. Infiniti issued TSB ITB17-004a (EM16-006a), covering all 2016 Q50 and 2017 Q50 built before September 7, 2016 (2017 Q60 built before May 27, 2016), with a belt alignment check and an A/C compressor re-alignment procedure. Nissan later revised the lower smooth idler pulley with raised lips to keep the belt captive — the design that shipped on the RZ34 Z.

The turbocharger center bearing on the 3.0L twin-turbo VR30DDTT can wear prematurely and let engine oil leak internally past the bearing seals into the exhaust and intake tracts. Oil burning in the exhaust produces heavy white or blue smoke, fouls the catalyst, and trips the MIL. In severe cases the turbo loses boost control and the internal components come apart, which can send debris downstream. Infiniti acknowledged the defect with a turbocharger emission warranty extension covering 2016-2018 Q50 and 2017-2018 Q60, extending coverage on the turbocharger assembly to Full Useful Life — 10 years or 120,000 miles, whichever comes first — when the failure presents as white smoke or an oil leak with a MIL-on condition.

The M274 four-cylinder in the 2.0t burns noticeably more oil than owners expect, and consumption climbs with mileage. Reports commonly describe roughly a quart per 3,000 miles once the car passes 60,000 miles, with worse cases burning a quart every 1,500 miles. The usual contributors are piston ring wear and coking, valve stem seal hardening, and the crankcase ventilation system pulling oil vapor into the intake. Because owners rarely pull the dipstick between services, they often do not notice the loss until the low-oil warning appears, and running the engine chronically low is what turns oil consumption into timing chain and bearing damage.

The front passenger seat's Occupant Classification System weighs and classifies the occupant to decide whether the passenger frontal airbag should be armed. On affected Q50 sedans the OCS can misclassify a normally seated adult as a child, or read the seat as empty while someone is sitting in it, and switch the passenger airbag off. The passenger airbag status light on the console reads OFF with an adult belted in. In a crash the passenger frontal airbag will not deploy. NHTSA campaign 16V244000 covers 2014-2017 Q50 and 2014-2016 Q50 Hybrid among a large group of Nissan and Infiniti vehicles.

A supplier error in the In-Vehicle Connectivity software inside the telematics control unit (TCU) cuts accessory power to the audio/video control unit when privacy mode is switched on. If privacy mode is enabled and the car then is not started for 14 days, the rear-view monitor, navigation screen and touch screen cannot be operated on the next start, so no rear-view image appears when the car is shifted into reverse. The vehicle fails to comply with FMVSS 111, the federal rear visibility standard. Only about 302 Q50s built January 20 to February 4, 2021 are affected. NHTSA campaign 21V599000 covers 2021 Q50, Q60, and QX80; Nissan's internal number is R21A9 and letters were mailed September 14, 2021.

Q50 sedans with the 2.0L turbo four use a saddle-shaped fuel tank with a transfer system that moves fuel between the two lobes. Incorrect Fuel Pump Control Module software allows the main tank lobe to run too low to feed the engine even though usable fuel remains on the other side and the gauge still shows fuel available. The result is an engine stall while driving, typically at lower indicated fuel levels. NHTSA campaign 17V476000 covers 2016-2018 Q50 and 2017 Q60 with the 2.0L engine; the recall began August 29, 2017.

A batch of front steering knuckles and rear axle housings left the supplier without proper heat treatment, leaving them below the required strength. The weakened parts can deform on impact — a curb strike or pothole that a sound component would shrug off — resulting in loss of steering control or, in the worst case, wheel separation. NHTSA campaign 21V402000 covers certain 2021 Q50 along with 2020 Murano and QX60, 2021 GT-R and QX50. Owner notification letters were mailed July 26, 2021.

On rear-wheel-drive Q50 Hybrid sedans the propeller shaft, built to a changed supplier specification with reduced fatigue strength, can crack and fracture at the press-fit joint of the ball yoke. When the shaft breaks the car loses all drive power without warning, and because the parking pawl in the transmission is no longer connected to the rear wheels the vehicle can roll away when shifted to Park unless the parking brake is set. NHTSA campaign 24V470000 covers 2014-2018 Q50 Hybrid two-wheel-drive vehicles along with several related M and Q70 models; Infiniti's internal campaign numbers are R24A5 and R24A7. Owner notification letters were mailed August 13, 2024. AWD cars are not covered by this campaign.

Owners of early Q50s report the dual-screen InTouch system locking up, restarting on its own, or losing navigation and audio. Infiniti ran a voluntary service campaign on 2014 Q50s to update the InTouch software.