2021 Audi Q7: sudden loss of power

Filed Sep 15, 2026 · Engine, Fuel system · OK

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. That it is not only an environmental concern, but a huge safety concern. I have contacted Audi America twice now regarding this and ZERO has happened.

Filed Mar 10, 2026 · Electrical · MA

I am submitting this complaint regarding a safety-related recall on my Audi Q7 involving the alternator. The wording of the recall is significantly underplayed, written off as an emissions issues. When in reality this is a life threatening flaw in the alternator. It is highly concerning that Audi isn’t being transparent with people who are driving these cars and risking their lives while doing so. This is not simply emissions, in reality, the car can totally malfunction while in operation. The entire electrical system fails and the car completely stops responding to the driver, fully stops and dies no matter where you are driving or at what speed. While driving on the highway, my vehicle experienced a catastrophic electrical failure caused by the recalled alternator, which caused the car to completely stop and it would not restart in any way. This created a life-threatening situation for my family and me. As a result of this electrical failure, the vehicle’s battery was damaged, and Audi has acknowledged coverage of 90% for the battery repair. However, the voltage converter, which is part of the same charging system, was also damaged during the same event. Audi is refusing coverage for the $1,600 repair of the voltage converter, despite the damage being caused directly by the alternator failure. I believe this represents a significant safety risk, as the vehicle’s sudden loss of power could lead to serious injury or death. Additionally, the recall itself caused secondary damage that is being denied coverage, which is unfair and unsafe. I am requesting that the federal safety agency review this matter as a safety defect/recall-related failure, and ensure the manufacturer addresses all consequences of this recall-related defect, including coverage of secondary damage like the voltage converter.

Filed Dec 15, 2025 · Engine · GA

- 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. - I do not know if the dealer delivered the involved parts to the manufacturer or insurance representative for inspection. Police or others did not inspect it. - There were no warning lights, messages, or other symptoms of the problem prior to the failure. It was identified by the Audi technician on 5 November 2025 while the vehicle was in the dealer for other services. The failure occurred at 47,855 miles which is far below the average lifespan of a water pump or vacuum system.

Filed May 27, 2025 · Brakes, Electrical · NJ

I am reporting a severe defect in my 2020 Audi Q7 involving “coolant migration” due to a faulty water pump, a known issue in Audi models (Q7, S4, A6, 2013–2022). This poses critical safety risks due to sudden failure with minimal warning. My out-of-warranty Q7 showed minor coolant fouling near a solenoid, with normal coolant levels and no fluid added. The dealer quoted ~$6,000 to replace the water pump and vacuum system. This defect is highly dangerous due to: Sudden Power Loss: Coolant in the vacuum system impairs solenoids and lines, disrupting engine/turbo function. This can cause abrupt power loss, risking loss of control in traffic or at high speeds, potentially leading to collisions. Catastrophic Overheating: A failing water pump may halt coolant circulation, causing rapid engine overheating without warning, risking sudden engine shutdown and stranding drivers in hazardous conditions like highways. Brake Assist Failure: The vacuum system powers the brake booster. Contamination can reduce braking effectiveness, increasing pedal effort and stopping distances, heightening collision risks in emergencies. Emissions Control Issues: Coolant fouling affects PCV and EVAP systems, causing misfires, stalling, or increased emissions, potentially triggering check engine lights and compromising engine stability. Undetectable Progression: The defect often shows no clear symptoms or warnings until severe damage occurs. My vehicle had only minor fouling that could only be detected by visual inspection, yet extensive repairs were needed, indicating the issue’s stealthy nature, which prevents timely driver intervention. Systemic Issue: Forums and a class-action lawsuit confirm this defect across Audi models, yet owners face high repair costs post-warranty. This defect endangers drivers and others by risking vehicle failure, impaired braking, and unstable performance. I urge the federal safety agency to investigate and mandate a recall or extended warranty.

Filed Nov 24, 2023 · Driver assistance, Electrical · NJ

Per carfax, my preowned 2021 Q7 with 9k miles has had several visits to audi dealerships. The car was eventually used for a buy back. That said, Audi USA "fixed" the vehicle and sold it. The car is NOT fixed and as the new owner I've waited 2 weeks after buying this car to drive and possess it only to have the battery warning light back on the dashboard after taking possession today. The car was previously at an audi dealership before it was cleared to be shipped to me. It seems Audi is unable to fix this car. I will need to tow it now to another audi dealership as I'm afraid the car will lose all power during any attempt to drive it back to a dealership.

Filed Aug 2, 2022 · Fuel system · TX

I am writing to report on the results of a call on 08-01-22 to Audi USA regarding the current recall on Audi Q7 automobiles. I asked if the car was safe to drive and the representative could not answer the question. Her comment was that Audi has not issued a Stop Drive Action. The recall notice states ". . .there may be a sudden loss of engine power or the vehicle may break down without a warning appearing beforehand." This would seem to indicate that it is not safe to drive the vehicle. Our vehicle meets all the criteria mentioned in the recall as being effected. However, the Audi USA representative instructed me to contact my dealer to get the car assessed. The dealer was contacted and we were told they are waiting on guidance from Audi USA and there was no reason at this time to bring the car in for evaluation. In short, we are very concerned about driving this car from a safety standpoint and Audi USA has done nothing but identify the problem without any solution as of today. It should be noted that we have not experienced any problem yet, but given the unknowns of this situation, we are hesitant to drive the vehicle. Any help in causing Audi to resolve this problem would be greatly appreciated.