Engine & cooling

Audi A6 Allroad Engine problems by year

5 complaints filed with NHTSA about the Audi A6 Allroad's engine & cooling. Stalling, loss of power, oil consumption, overheating, head gaskets, timing chains and engine failure.

Engine complaints by model year

2020 52021 2022 2023 2024 2025 2026

Year	Engine complaints	Crashes	Injuries	Recalls
2021	5	0	0	0

Latest A6 Allroad engine complaints

2021 Audi A6 Allroad Electrical system Engine & cooling Fuel system

While operating the vehicle under normal driving conditions, the vehicle suffered an immediate, un-commanded loss of engine power and throttle response. The vehicle displayed a critical dashboard restriction stating: "Maximum engine speed 2500 RPM", forcing an emergency limp-home mode that instantly created a roadway collision hazard. Simultaneously, the vehicle's primary safety and convenience systems dropped completely offline, displaying synchronized, consecutive malfunction alerts for the Central Locking...

Read the full complaint

System, Audi Pre Sense (Distance Monitoring), Cross Traffic Assist, and Lane Change/Blind Spot Warning systems. A subsequent professional diagnostic scan confirmed that the vehicle's Engine Control Unit (ECU) has hard-logged active manufacturer fault codes P310A (Low Fuel Pressure Regulation - Fuel Pressure Fluctuates) and P310B (Low Pressure Fuel Regulation - Fuel Pressure Outside Specification). These synchronized electrical and drivetrain failures occur intermittently, yet have specifically occurred multiple times following exposure to moisture, including rainfall, winter slush, and standard car washes. The identical electrical system dropouts were officially reported to two authorized Audi dealership service centers during its active warranty window, but the underlying system failures remain uncorrected, leaving a recurring safety hazard unaddressed.

2021 Audi A6 Allroad Engine & cooling

The contact owns a 2021 Audi A6. The contact stated while driving at an undisclosed speed, the vehicle overheated. The engine overheating and the low coolant warning light illuminated. In addition, the engine seized. The vehicle was taken to the dealer where it was diagnosed with a coolant leak and a failed coolant pump vacuum. The contact was informed that the coolant pump vacuum assembly needed to be replaced. The vehicle was not repaired. In addition, the contact was informed that the failure was a known failure...

Read the full complaint

of the vehicle. The manufacturer was made aware of the failure and a case was filed. The contact was advised to contact the NHTSA Hotline and report the failure. The failure mileage was approximately 80,000.

2021 Audi A6 Allroad Engine & cooling

Thermostat housing and oil cooler bracket leaking coolant with only 56k miles on the car

2021 Audi A6 Allroad Steering Electrical system Engine & cooling

Car reported an engine restarter issue (with battery symbol) and recommended to contact the dealer. Car next shut down automatic restart system, and air conditioning stopped working. Within a short period of time (same day), the car listed a red battery symbol and advised to stop the car. After doing so and contacting the Audi roadside, the car was listing a series of issues on multiple symptoms while also saying in the warning message "still okay to drive". These systems included steering, braking, and what seemed...

Read the full complaint

to be other sensors the car powers. Finally (and within 5 minutes of the previous message of being okay to drive), the warnings were continuous and started including the transmission. The car stopped accelerating (we were on the expressway) and we thankfully got to the side of the road. This was an enormously dangerous situation as the car became fully disabled and we were subject to limited options of relief from a major traffic area. Within 30 minutes of being disabled, no electrical charge was present in the car, including emergency flashers, making the situation more dangerous as it was nighttime, so we had to abandon the car and walk down the expressway to find a hotel. Could not even put the car in neutral for the tow. Service is initially reporting a failure of the restart generator. This appears to be an alarmingly common issue with Audis.

2021 Audi A6 Allroad Transmission & drivetrain Engine & cooling

At a highway speed of 50 MPH the transmission completely disengaged. I was driving on a busy highway with no shoulder. The vehicle continued to coast until I was forced to stop in an unsafe location. I placed the car in park, then in drive, and it was still disengaged. I needed to turn the car off, turn it on and it drove normally. Before I was able to bring it into Audi it occurred a second time on a bridge. I needed to perform the same steps (park, turn off, turn on) to begin driving again. Audi 'repaired'...

Read the full complaint

the vehicle. One month later it happened again. A service report cited this as a known issue. It created a significant risk to safety considering all events occurred at highway speed with no warning.

Source: U.S. National Highway Traffic Safety Administration (NHTSA) complaints and recalls, checked daily. Complaints are owners' own reports and are not verified. How we use the data