The 2019-2021 XC90 T6 and T8 with the 2.0L supercharged and turbocharged engine can suffer piston-ring carbonization, causing oil consumption of about one quart every 1,000-2,000 miles. Watch for low-oil warnings between services, fouled spark plugs, and catalytic converter damage. If left untreated, severe cases can lead to catastrophic engine failure. Piston-ring replacement is typically $4,000-$8,000, while complete engine replacement can run $9,000-$14,000.

On 2019-2021 XC90 T6 and T8 models, the Roots-type supercharger can develop bearing or clutch failure, most often reported on 2019-2020 cars. You may hear a high-pitched whine or grinding noise on acceleration, followed by reduced power and eventual supercharger seizure. If debris enters the engine, it can score cylinder walls and require full engine replacement. Supercharger assembly replacement is about $2,800-$4,500 at an independent shop and $4,000-$6,000 at a dealer.

The high-voltage battery control module in 2019-2023 XC90 T8 Recharge models can fail to detect internal shorts or trigger hybrid system shutdowns, and NHTSA recall 20V-335 addressed fire risk. Symptoms include hybrid system failure warnings, loss of electric-only drive, and possible sudden powertrain shutdown. Affected recall vehicles are repaired free, while BMS replacement outside the recall is $1,500-$3,000.

2019-2021 Sensus and 2022-2024 Google Android Automotive systems commonly freeze, reboot, black-screen, or lose backup camera and climate controls, while the 2026 model received new Snapdragon hardware to improve responsiveness. A dealer software reflash is usually $150-$400, and head-unit replacement ranges from about $1,200-$2,500 for Sensus units to $1,800-$3,200 for Google-based units. If the screen fails while driving, navigation, camera, and climate adjustments can be unavailable until the system recovers.

2019-2023 XC90s with optional Four-C air suspension can develop ride-height sensor corrosion and compressor overheating, causing the vehicle to sag overnight or drop to the bump stops. Watch for suspension failure warnings, continuous compressor cycling, and a tilted ride after parking. A single air strut costs $1,200-$2,000, a compressor $900-$1,600, and a height sensor $400-$700, while a full dealer rebuild can reach $5,000-$8,000. Repeated compressor failure is common if the root cause is ignored.

The A/C evaporator core in 2019-2022 XC90s can leak refrigerant internally, most often reported on 2019-2020 cars. Symptoms include warm vent air, a sweet chemical smell in the cabin, and the system needing frequent recharges. Because the evaporator sits behind the dashboard, replacement costs $1,800-$3,000 at a dealer or $1,200-$2,200 at an independent shop, and the leak can also shorten compressor life.

2019-2023 XC90s with City Safety can falsely apply full braking at highway speeds when the radar and camera system misreads shadows, guardrails, or overpasses. Drivers may see a City Safety intervention message with no obstacle present, and the sudden stop has caused rear-end collisions. Volvo addressed it with software recalibration; a dealer update is typically $100-$250, while collision damage from an event can cost $1,500-$5,000 or more.