I am reporting an ongoing cooling-system/water-pump issue with my 2020 Audi Q8, approximately 75,000 miles. The problem began when the vehicle repeatedly displayed a low-coolant warning. Inspection confirmed the coolant level was very low and a significant problem involving the coolant pump/vacuum system was diagnosed. The water pump was subsequently replaced. After the repair, the vehicle initially appeared normal, but problems continued. I experienced engine sputtering/rough running and the vehicle felt as though it might stall while stopped at a traffic light. A Drive System Malfunction/check-engine warning appeared, and cruise control/driver-assistance functions became unavailable. The check-engine light has continued to return intermittently. There was also an issue with a loose cap following the water-pump repair, which was corrected. Despite this, the low-coolant warning later returned and the coolant reservoir was again confirmed to be low. Coolant was added and the vehicle was returned to the repair facility to locate a leak. The shop kept the vehicle for several days and ran it for approximately two hours while inspecting it but could not reproduce or locate a coolant leak. The check-engine light went out during testing but returned shortly after the vehicle was picked up and driven normally. A sensor was also replaced based on a diagnostic code, but the check-engine light returned afterward. I have now spent more than $3,000 attempting to correct these issues, yet the cause of the recurring coolant loss and warning lights has not been determined. I am concerned that this may represent a recurring defect involving the water pump/cooling or related vacuum-control system. My primary safety concern is the possibility of unexpected coolant loss, overheating, engine malfunction, reduced power, or stalling while driving. I am requesting that this complaint be documented and investigated for similar incidents involving 2020 Audi Q8 vehicles.
NHTSA complaint #11758701 — an unverified report by a vehicle owner.
On July 4, 2026 in the early evening, I was driving in the HOV lane of the freeway when the engine abruptly lost power. There was a warning light that came onto the dashboard but I did not see what it said as I was solely concerned about moving safely off to the shoulder in moderate traffic. Once I pulled to the shoulder, I restarted the vehicle and was able to drive home safely. What put my wife and I in great danger was the vehicle losing power without warning when driving on the freeway and having to navigate safely to the shoulder in traffic without having acceleration power. I took the vehicle into the Audi Ontario dealer on July 6 for a rearview camera recall notice and to address the engine problem. I did not drive the vehicle after the July 4 incident but the loss of power did not happen again after I restarted the engine nor when I drove it to the dealer on July 6. The dealer notified me the next day that they could not recreate the engine problem and that the engine automatically turns off after coming to a stop. I explained I had not come to a stop, that I was driving at about 80 MPH with both hands on the steering wheel. I asked about what trouble codes they found and if I could have a print out since this was a safety concern and the vehicle only has 1,500 miles on it. The loss of propulsion was not the auto turn off when coming to a stop. They kept the vehicle for further review and I have not heard back as of July 14. I called to make inquiry and they are supposed to call me back. My concern is not only for me, but also for anyone that has this vehicle year, make, and model - the next person may not be so lucky to navigate to safety if it happens to them.
NHTSA complaint #11750275 — an unverified report by a vehicle owner.
I was driving my car would not accelerate on the highway and it almost caused me to get into an accident with my niece in the car. When I took the car to Audi this is what I was told my the service adviser. “Good afternoon. The technician has been looking into the vehicle and has found the cause of the issue. He has found the coolant water pump has failed internally causing coolant to leak internally into the vacuum system. This is causing the vacuum to be blocked for the turbo and thus causing the sluggish feeling when accelerating. In order to fix, the water pump and all compromised vacuum system components need to be replaced. It is a rather extensive job unfortunately.” My car only has a little over 45 thousand miles. Audi should be responsible to fix this problem because they sold this car knowing the water was faulty in these models. I recall should have been put out. I was quoted $6,000 to fix this problem.
NHTSA complaint #11741357 — an unverified report by a vehicle owner.
My car is a 2019 Audi Q8 3.0L V6 with only 41,831 miles. My emergency light went on and I brought it my locat Audi Dealer. The inspection revealed that the coolant pump was leaking internally, contaminating the entire vacuum system with coolant. This is not a maintenance failure or the result of owner neglect. It is a well-documented, inherent design defect in the EA839 3.0T engine platform that powers the 2019 Q8, a defect that Audi of America has acknowledged through multiple Technical Service Bulletins. Specifically, the EA839 water pump uses a vacuum-operated diaphragm to control coolant flow. When the pump's internal seals fail — as they predictably do — coolant migrates directly into the engine's vacuum system, contaminating components far beyond the pump itself. Industry experts and Audi forums alike describe this failure mode as inevitable on this platform: not a matter of if, but when. This is a design defect manifesting at a fraction of the mileage at which any reasonable owner would expect a cooling system component to fail. Audi of America has issued multiple TSBs addressing coolant pump failures on this exact engine platform, and previously extended warranty coverage for Q7 and Q8 vehicles, including those built during the same production window as the vehicle in question. Our concern is this issue can cause the engine to seize while driving and Audi's repair costs for this known issue have been quoted minimally at $5,519.76
NHTSA complaint #11736636 — an unverified report by a vehicle owner.
I own a 2019 Audi Q8. The vehicle was in the dealership’s possession for approximately three (3) weeks for service. During that time, I was not informed of any significant mechanical concerns or issues. After retrieving the vehicle, it displayed an oil pressure warning while in operation. I immediately returned the vehicle to the dealership for evaluation. At that time, the dealership added oil (“topped off” the vehicle) and released it back to me without identifying or addressing the underlying cause of the warning. Following this, I made multiple attempts to have the vehicle properly diagnosed. I experienced difficulty obtaining assistance, including calls being disconnected, and I was not provided meaningful support or a thorough evaluation of the issue. Shortly after leaving the dealership, the vehicle began producing abnormal knocking noises and rapidly became unsafe to operate, requiring it to be towed. This situation presents a significant safety concern, as a sudden loss of power or drivability while driving can increase the risk of an accident, particularly in traffic conditions where maintaining speed is necessary. The condition has since been confirmed by a service provider as a major mechanical failure. Additionally, I have received documentation from the manufacturer indicating a known issue related to piston skirt defects associated with this vehicle. Despite the vehicle being in the dealership’s possession for an extended period, this issue was not identified, diagnosed, or addressed. I was also not provided clear assistance or guidance regarding potential warranty consideration related to this known issue. The vehicle is currently available for inspection upon request.
NHTSA complaint #11734916 — an unverified report by a vehicle owner.
CHARGING SYSTEM DEFECT: The manufacturer-supplied portable charger (rated 9.6kW at 240V/40A) delivers only 7.4kW — a 23% shortfall. The authorized dealer confirmed this measurement in March 2026 but refused to repair, stating "no issues." The charging rate also degrades over time without manual reset. The vehicle also intermittently fails to charge at DC fast charging stations — it begins charging, then stops within minutes displaying "Malfunction of charging" error. Other EVs charge normally at the same stations. SAFETY RISK: Charging failures create a stranding hazard. The vehicle can fail to charge at public stations without warning, leaving the driver unable to complete trips. REPAIR HISTORY: 5+ visits to two authorized dealerships over 10 months (May 2025–March 2026), 16+ days out of service. No fix — returned each time as "no fault found" despite video evidence of failures shown to dealer at every visit. Manufacturer corporate support also failed to resolve. Dealer found DTCs for charger communication faults. A demand letter was sent to manufacturer — no response received. Vehicle and charger available for inspection.
NHTSA complaint #11725412 — an unverified report by a vehicle owner.
Piston slap issues. The manufacturer is aware of the engine failure issues. They extended the engine warranty coverage from 50k to 80k miles knowing that the engine piston slap is an extreme issue but they won’t issue a total and complete recall. Owners have to identify that issue and have to specifically bring it in to have it bore scoped. If an owner isn’t aware of the noise and goes over the 80k miles then they are not held responsible for the complete and utter engine destruction.
NHTSA complaint #11715703 — an unverified report by a vehicle owner.
Engine failed at 78,990 from an manufacturer defect that Audi knows about for the last couple of years. Audi extended warranty due to the failure to 8 years or 80K miles. The engines can lock up due to a piston failure in the scored cylinder walls causing a crash. Oil consumption is very high causing vehicle to burn oil and not pass smoke test. Please investigate these engine failure and manufacturer defects with this engine in multiple vehicles 3.0L turbo gas engine thanks
NHTSA complaint #11712895 — an unverified report by a vehicle owner.
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.
NHTSA complaint #11711800 — an unverified report by a vehicle owner.
I was having noise from engine and and I received a letter from extended warranty for an production defect in piston skirt. I sent my car for an evaluation in the Audi of Manhattan and I was told that my car falls under the engine piston skirt defect.i have the pictures from Audi Manhattan inspection that the engine piston walls have scratches.i was denied coverage under extension warranty because my car was over 1752 mile over the extension warranty.this is and production engine defect and can be stranded any time soon in the high way or any other street putting me and My family in danger and any other people driving around my car if that engine stops in the middle of the street. My car has 81752 miles and the extension warranty was up to 80000 mile or 8 years. The extension warranty came to late almost after 6 years ,as this is an known problem with those engines EA839 that is found in audis Porsche VW Tuareg ect.
NHTSA complaint #11698834 — an unverified report by a vehicle owner.
Water pump failed coolant leaked all over the vehicle five years old and a $7500 repair vacuum seals and most of the engine is damaged from the coolant. I have the video from the dealership but can’t upload
NHTSA complaint #11693465 — an unverified report by a vehicle owner.
Catastrophic engine failure on Audi Q8 3.0L turbo. Per service manager it a know issue and Audi just sent out a letter extending engine warranty to 80,000 miles. Per Audiworld forum Audi is replacing some engines and charging some owners $27,000 Audi needs to be investigated and held accountable for people that have faulty engines and can make the car crash when engine locks up
NHTSA complaint #11689306 — an unverified report by a vehicle owner.
engine begin to misfire and felt like it was ready to stall. within a minute of the misfiring the engine light came on. i was in the middle of highway struggling to get my vehicle to the dealership where purchased which thankfully was only 5mins away. tech heard noise coming from fuel pump near the engine and recommended replacing along with spark plug. after replacing tech advised me to take my vehicle to audi to perform a software update that will correct the misfire and prevent the MIL from illuminating. Got that done to only be presented with a knocking noise again a month or two later. Took my car back to Audi to run a full diagnostic to find out my engine is in early engine failure due to metal shavings in the oil filter. tech states shavings in the oil could originate from the fuel pump failure and the debris would have traveled into the engine oil causing critical damage to the engine.
NHTSA complaint #11688191 — an unverified report by a vehicle owner.
being quality Engineer, why is this thing failing , and why are there no recalls? Amazing how they design these things to fail right at 50k miles. From what I hear, the audi's are notorious for not making these replacements simple and specialized tools are needed. I wouldn't change anything engine related unless you have issues like engine shaking, or rattling sounds stemming from the engine mounts. And if you get major work done, it is probably best to go to the dealers and pay the extra to make sure it will be taken care of properly! numerous same issues engine mounts after 50k MIles
NHTSA complaint #11669188 — an unverified report by a vehicle owner.
The vehicle is a 2020 model with less than 55k miles and experienced coolant leaks. Specifically, the water pump was faulty and leaked causing coolant liquid to leak in additional lines and gaskets. The repairs resulted into costs upwards of $5k. When I first brought into dealer, the service rep mentioned that the fluctuating coolant lines wouldn’t be an issue but I further pressed them on doing a pressure test to which the issue was discovered. This is a huge safety problem if my engine was to overheat or face and other issues on the leak. I’ve never heard of a water pump going bad so quickly.
NHTSA complaint #11662231 — an unverified report by a vehicle owner.
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.
NHTSA complaint #11656169 — an unverified report by a vehicle owner.
- The water pump failed, leading to a coolant leak and potential engine overheating. The failed component is not available for inspection, as it was replaced by an independent repair shop after the dealership quoted an excessive price and could not complete the repair in a timely manner. - A failing water pump can cause engine overheating, sudden power loss, or complete engine failure while driving, which increases the risk of an accident. Additionally, I noticed the smell of coolant inside the cabin, which could indicate a leak that might pose a fire hazard or expose occupants to coolant fumes. - Yes, the issue was diagnosed by an Audi dealership (Audi Northlake), which confirmed that the water pump had failed and needed replacement. Due to their high repair quote and scheduling delays, I had the repair completed at an independent service center, which also confirmed the failure and replaced the water pump. - The issue was confirmed by an Audi dealership but was not formally inspected by Audi corporate, law enforcement, or an insurance company. - Yes, I noticed a coolant smell inside the cabin for a few days before taking it to the dealership. However, there were no warning lights or messages on the dashboard before the failure was diagnosed.
NHTSA complaint #11643976 — an unverified report by a vehicle owner.
The alternator failed causing the vehicle to shutdown in the middle of traffic. I was on a surface road not the highway so I was able to get local police to assist. When it failed there was no car electrical system function, so I could not even turn on my emergency blinkers. This is apparently very common on Audis, as the same part was used to replace the alternator…. It took a month for the dealership to get the part in stock.
NHTSA complaint #11582506 — an unverified report by a vehicle owner.
I was driving home from work when all of a sudden I got error messages: Electrical system malfunction! Please contact service; Start/ stop system: malfunction! Function unavailable. Please contact Service, yellow battery light and the car died. None of the safety features, locks, engine, or air condition worked and the car had to be towed to the dealership. Within 1 mile of the lights appearing the car died, putting my safety and those on the road at risk. I left in the middle of the street and had it towed a few hours later. I spoke to the dealership and was diagnosed and confirmed as a alternator- starter-generator issue and reading the Audi threads it is a common issue. The car has about 38,000 miles. I am the second owner and have had the car for less than 6 months and it has been well maintained.
NHTSA complaint #11578605 — an unverified report by a vehicle owner.