2021 Audi Q7 Engine Problems

Mileage when the problem started

Owner reports

Selected complaints filed with NHTSA by 2021 Audi Q7 owners, lightly cleaned up (personal details are redacted by NHTSA).

The contact owns a 2021 Audi Q7. The contact stated that while driving approximately 50 - 55 MPH, the Check Engine light had illuminated. The vehicle was taken to the dealer, who diagnosed code PO299, which referred to coolant migration into the vacuum system. The contact was unable to provide the exact parts that were needed for repairs. The vehicle was not repaired. The manufacturer was informed of the failure. The manufacturer opened a case regarding the issue. The failure mileage was approximately 60,000.

While driving the vehicle, error messages began appearing on the in-panel dashboard display. At first, a yellow/orange battery icon appeared with the message "Electrical system: malfunction! Please contact Service". Within an hour, the car experienced another electrical system malfunction (red battery icon appeared with the message "Electrical system: malfunction! Safely stop vehicle") along with a host of other error messages (Brakes: malfunction, Steering: malfunction, Parking brake: malfunction, Vehicle lights: malfunction, Stabilization control (ESC/ABS): malfunction, Drive system: malfunction, Transmission: malfunction). The car was undrive-able at this point, coasted to a stop and could not be restarted while on an active roadway. The car had to be towed to the dealership, where it still remains today. …

Driving on highway at 70 mph and high engine temp light came on. Said to pull over and continue to run car until temp decreased. I got over as quickly as I could ( no more than 1/4 of a mile) and sat on side of PA turnpike as engine cooled. I was at bottom of an exit ramp. I slowly proceeded up the ramp and warning came on again and red temp light reached again. I pulled right into the gas station at top of TP exit ramp. It still said to continue to run the car. I sat with my son in the car and ran the car in the shade. The temp was decreasing and then all my electrical lights came on, yellow battery warning light on and then suddenly the red battery light and all systems failed. Car turned off. Called AAA to take to my mechanic as Audi was a 3 hour wait for a tow and 3 weeks for service appointment with no loaners available. My certified mechanic said water pump completely dislodged. …

- Engine water pump failure and coolant intrusion into the vacuum system. Parts were replaced on 5 Nov 2025 and possible still at the dealer's location. - The defect poses the following safety risks: It resulted in contamination of vacuum lines; potential for sudden engine stalling or loss of power while driving; potential for catastrophic damage to engine-management systems dependent on vacuum integrity; potential for damage to emissions and combustion-control systems; potential for reduced braking system performance if vacuum supply is compromised, expensive and unexpected component failures, and possible recurrence since the cause appears related to design rather than normal wear. Any failure can create cascading hazards affecting safety-critical functions. - The problem was confirmed by an authorized Audi dealer. Dealer name and contact info can be provided upon request. …

My independent repair shop has just diagnosed a coolant leak weeping from the vacuum line connection at the water pump; they referred to this problem as "coolant migration". As documented extensively by Audi in Technical Service Bulletin 19-23-45 (2070349/2), this indicates an internal seal failure of the water pump, causing pressurized engine coolant to migrate directly into the vehicle's vacuum system. While I understand that my vehicle is technically past its 4-year factory warranty timeline, a mechanical failure of this nature at just 43,000 miles is highly premature and points to a known manufacturer design defect rather than standard wear and tear. More importantly, this defect poses an immediate, severe safety risk. Because the vacuum system directly services the power brake booster, the migration of coolant into these lines risks catastrophic contamination of the braking system. …

I have heard a knocking and experienced sudden loss of power while driving- not electrical loss, but vehicle suddenly slows down and unable to pick back up speed effectively creating a safety concern when driving- especially at on ramps. A warning light comes on and then it will go off randomly with the loss of power. I have taken it in multiple times and was told it is an emissions issue and a vacuum hose issue that allows fluid to get into my turbos or something along those lines. I have both been told by my Audi service advisor and done my own research and seen there have been issues with previous years and ultimately a recall was done to fix those- My vehicle is the 1st year following previous recalls. I have been told by the service professionals that they are at a loss whey a recall has not been issued on this issue again. …

While driving with my 4 year-old daughter a notification appeared on the driver display that there is an "Electrical Malfunction" and to call the service department. A few minutes later, while actively driving on the same busy road in my town, the vehicle completely turned off, including the power steering and ABS breaks. I was stuck in the middle of a busy intersection with no hazard lights and no ability to even shift the vehicle into neutral to move it. I was genuinely concerned for my safety and the safety of my daughter, as we were stranded in the middle of a busy intersection during rush hour. It was a harrowing experience to say the least. Eventually we had the vehicle towed. When I called Audi, they informed me that they suspected it was the "starter generator" and that they were aware of the issue, but this was the first I had heard of it. …

During commute dash lit-up with "central indicator light", "Vehicle starting system; malfunction! Please contact Service" warning notice, "Audi pre sense" yellow-lit dash warning light, yellow-lit battery warning light that alternated to red-lit battery warning light. AC automatically shut off, radio shut off, was able to limp vehicle home. Restarting the vehicle gave a "Battery low voltage" reading then a vehicle failure "immediately turn vehicle off when safe" message followed by the "Vehicle starting system; malfunction! Please contact Service" warning notice. Towed Audi to local Audi shop in Charlottesville, VA, where it was diagnosed with starter generator failure, part was reportedly ordered on 27 July 2024; no indication as to whether the part has arrive at Audi shop. No details on the battery as of 01 August 2024.

El carro fue comprado en febrero 2024 en greenway ford inclui un paquete de cambio de aceite,rotacion de llantas y cambio de los limpiabrisas.esto ha sido un dolor de cabeza. cada vez que se le realiza el servicio sale con la luz del ingenier prendido, en la computadora de auto zone aparece TURBOCHARGER INTERCOOLER(P0299). Ademas El asiento del pasajero esta siempre muy caliente el carro gasta demasiada gasolina y esta perdiendo velocidad,en verdad no se si el carro esta gastando aceite, ya que reci n cambiado el sistema me mostro falta de aceite .o el consecionario no cambio el aceite correctamente..

Multiple warnings indicating to contact dealer (Lane departure, adaptive cruise control, collision avoidance, electric system malfunction, steering malfunction) then a few minutes later transmission failure and engine failure imminent.... attempted to move out of traffic. Luckily, I made it to the right lane before the steering shut down, then the transmission failed (stepping on the gas caused the engine to rev, but no power was delivered to the wheels), and last the car completely died. Had to have it towed to dealership. Dealership confirmed that the starter/generator failed.

Engine complaints in other Q7 years