2021 Audi Q8: sudden loss of power

Filed Jan 30, 2026 · Transmission · SC

Audi Q8 failed water pump leading to severe loss of power and a major safety issue. I was merging on a very busy highway when I had loss of power with my children in the vehicle. This was alarming as I was not able to accelerate as anticipated and had no warning/notice that this was going to occur, and others around me did not know what was going on as well. This is a known complaint and issue in these vehicles and a major safety issue. Audi should stand behind their quality and it is dissapointing costly repair that shouldn’t be needed at 50 k (right outside of warranty). This issue can cause a detrimental accident.

Filed Jan 19, 2026 · Engine · FL

The engine (internal mechanical failure) malfunctioned. The vehicle developed a persistent ticking/knocking noise from the engine bay, and the authorized Audi dealer diagnosed the issue as requiring a full engine replacement. The vehicle is currently available for inspection upon request. A catastrophic engine failure presents a risk of sudden loss of power, stalling, or engine seizure, which could occur while driving at speed or in traffic. This creates a potential risk of loss of vehicle control, inability to accelerate, or being stranded in unsafe conditions, endangering both the driver and other motorists. The problem was confirmed by an authorized Audi dealership, which diagnosed the vehicle and stated that a complete engine replacement is required. The estimated repair cost provided by the dealer is approximately $26,000 (so far in parts only). The vehicle has been inspected and diagnosed by an authorized Audi dealership. At this time, it has not been inspected by police or insurance representatives. Audi corporate has been contacted for review. The primary symptom was a persistent ticking noise from the engine bay, which began around late December 2025 / early January 2026. There were no immediate warning lights or dashboard messages at the onset of the noise. The noise progressively worsened, prompting dealer inspection and diagnosis.

Filed Sep 15, 2025 · Fuel system · 60,000 miles · FL

The contact owns a 2021 Audi Q8. The contact stated that while driving at various speeds, the instrument panel failed to operate. The contact stated that while driving 70 MPH, the failure recurred. The contact received notification of the federal safety agency Campaign Number: 25V201000 (Electrical System), and the vehicle was taken to the dealer, where the recall repair was performed; however, the failure recurred the same day while driving from the dealer. Additionally, the contact stated that the vehicle stalled while driving at various speeds. The vehicle was taken to the dealer, where it was diagnosed that the fuel pump had failed, but the vehicle was not repaired due to the cost. The contact stated that while driving 50-55 MPH, the messages "Loss of Power", "Reduced RPMs to 3,000", and other unknown messages were displayed, and the vehicle stalled. The vehicle was towed to the residence. The contact related the failure to the federal safety agency Campaign Number: 22V516000 (Fuel System, Gasoline); however, the VIN was not included. The vehicle was not repaired. The manufacturer was notified of the failures. The failure mileage was approximately 60,000.

Filed Apr 22, 2025 · Driver assistance, Electrical · CO

On April 2, 2025, while driving on Interstate 25, my 2021 Audi Q8 Premium Plus experienced a catastrophic engine and electrical failure. This included the generator system failing, which resulted in a complete loss of power, disabling all active safety systems (including electronic stability control, braking assist, and lane monitoring), as well as basic driving capabilities such as acceleration and steering responsiveness. The incident occurred without prior warning or diagnostic alerts, and the vehicle became immobile on the highway. The situation posed a serious safety hazard to both myself and surrounding drivers. The vehicle had an unresolved generator recall, which Audi later confirmed and completed after the incident. This event raises significant concerns regarding system reliability and pre-failure alert mechanisms in the Q8 platform.

Filed Jan 11, 2024 · Electrical · OH

The alternator on my Audi Q8 SUV died AS I WAS DRIVING IT, leaving my vehicle with no power. I was left to coast down the 50-60 MPH highway I was driving on into a turn lane, where the vehicle stopped and could not be restarted. My safety was put at risk because I was on a highway in a car that stopped operating suddenly and catastrophically. If I had not been able to coast into a turn lane, the car would have left me in a high-speed lane. I waited for a tow truck over two hours, the first hour inside the vehicle, the second outside on a small concrete lane divider. The last hour I spent directing live traffic to slow down and pass my vehicle, which was in the left-turn lane, and whose warning flasher lights had ceased working when the battery was depleted. The vehicle was towed to an Audi service department, where the vehicle was inspected, the failure diagnosed, and the failure corrected by replacing the alternator and recharging the battery. The first symptom of any problem was an error message the evening before when hands-free entry was denied (I had to use my key fob to enter the vehicle instead of placing my hand inside the door handle). Also, the dashboard displayed an error message directing me to contact a service department. In the morning, I called my local Audi service department to report the issue and was given an appointment time for the following morning. I had errands to run, so I took the vehicle on the aforementioned highway, when error messages indicating the loss of availability of various electrical and safety systems (e.g., Lane Departure warning, Lane Assist, Park assist, etc.) began to flash suddenly, one after the other, on my dashboard. The battery icon began glowing first yellow, then red, then flashing between yellow and red. There was one more message about the transmission being in trouble and that I should stop the car safely. At that moment, I lost powered forward propulsion and began to coast, as indicated above.