2021 Audi A4 Problems & Owner Complaints
Age-normalised, this year draws ~1.8 complaints per year on the road — ranking 10 of 11 Audi A4 years we track (1 = most complaints per year).
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What owners report
Electrical System is the most-reported problem area on the 2021 Audi A4, cited in 3 of 11 filed complaints (27%).
Forward Collision Avoidance is next (2 complaints, 18%), followed by Lane Departure (2), Power Train (2), Suspension (2).
Across all complaints, 3 report a crash, 1 report injuries.
The most safety-critical cluster is Vehicle Speed Control: 2 crash, 1 injury report(s).
Complaints by vehicle system
Owner complaints filed with the U.S. NHTSA for the 2021 Audi A4, grouped by the vehicle system each cites. A single complaint can name more than one system, so the group totals can add up to more than 11.
Electrical System 3
“The instrument cluster has stop working. Have to monitore vehicle information, Mileage, service, Safty notifications and general vehicle information from the Audi app.”
NHTSA complaint #11692106, 2025
“I have a 2021 audi a4 that is also being affected by the instrument cluster failure/recall. My model , a4 was not included but I am experiencing the same failure and this was reported to the dealership. An online search will show just how many people have issues with the instrument cluster. The instrument cluster screen just went out while driving. I have to monitor my functions via the app on my phone. The dealer wants to charge me full price when every other model in 2021 has been recalled for the same issue. The A4 should be added to the instrument cluster recall for 2021 audi.”
NHTSA complaint #11677729, 2025
“The main instrument cluster is not stable- it tries to start up then crashes. As a result, speedometer, rpm’s, gas tank gauge, etc are not available while driving. The screen displays blank with a red triangle, tries to start up then crashes again. This seems similar to Audi recall campaign 90VC, but for some reason the A4 was not included in the recall, but I’m having similar symptoms with my A4.”
NHTSA complaint #11667730, 2024
Unknown Or Other 3 1 crash
“The reversing image occasionally appears white screen phenomenon During the process of reversing, the reversing screen suddenly turns white and cannot see anything behind, which brings danger to the driver and others, causing danger to life and property. Apparently the dealer didn't take this seriously”
NHTSA complaint #11459964, 2021 · crash
“The instrument cluster has failed per the recall 90VC. Audi issued the recall for every model made in 2021 with the exception of the A3 and A4 and I believe this was a mistake as my instrument cluster has the same failure.”
NHTSA complaint #11680440, 2025
“The vehicle at 13,xxx miles on the high ways, and during stop & go traffic; vehicle begins to tremble, transmission and floor shakes, rpms are higher than normal, abnormal noises coming from engine (screeching), jerking on acceleration on the first gears, rough idle, happens only on highways after 1hr of driving. Can drive over 40 min without any check engine light turning on. No codes come up, while clearly having issues. After a day of being off, car goes back to normal without those issues, just vibrations and pulsing on idle. -happens on Texas highways where vehicle begins to have troubl…”
NHTSA complaint #11652167, 2023
Forward Collision Avoidance 2
“The instrument cluster has failed per the recall 90VC. Audi issued the recall for every model made in 2021 with the exception of the A3 and A4 and I believe this was a mistake as my instrument cluster has the same failure.”
NHTSA complaint #11680440, 2025
“I have a 2021 audi a4 that is also being affected by the instrument cluster failure/recall. My model , a4 was not included but I am experiencing the same failure and this was reported to the dealership. An online search will show just how many people have issues with the instrument cluster. The instrument cluster screen just went out while driving. I have to monitor my functions via the app on my phone. The dealer wants to charge me full price when every other model in 2021 has been recalled for the same issue. The A4 should be added to the instrument cluster recall for 2021 audi.”
NHTSA complaint #11677729, 2025
Lane Departure 2
“The instrument cluster has failed per the recall 90VC. Audi issued the recall for every model made in 2021 with the exception of the A3 and A4 and I believe this was a mistake as my instrument cluster has the same failure.”
NHTSA complaint #11680440, 2025
“I have a 2021 audi a4 that is also being affected by the instrument cluster failure/recall. My model , a4 was not included but I am experiencing the same failure and this was reported to the dealership. An online search will show just how many people have issues with the instrument cluster. The instrument cluster screen just went out while driving. I have to monitor my functions via the app on my phone. The dealer wants to charge me full price when every other model in 2021 has been recalled for the same issue. The A4 should be added to the instrument cluster recall for 2021 audi.”
NHTSA complaint #11677729, 2025
Power Train 2
“I am writing to report a persistent issue with my 2021 Audi A4, VIN [XXX] . I have been experiencing a noticeable vibration, humming, and shuddering sensation that occurs specifically when turning at slow speeds (e.g., in a parking lot or when making a tight turn at an intersection). This issue has been diagnosed at a dealership, and the diagnostic report from the service invoice dated 07/12/2025 noted "VIBRATION HUMMING SHUDDER WHILE TURNING." The vehicle's mileage at the time was 38,888 miles. Dealership diagnosed this issue as a failing AWD clutch system. I took the car to a different re…”
NHTSA complaint #11681029, 2025
“The vehicle at 13,xxx miles on the high ways, and during stop & go traffic; vehicle begins to tremble, transmission and floor shakes, rpms are higher than normal, abnormal noises coming from engine (screeching), jerking on acceleration on the first gears, rough idle, happens only on highways after 1hr of driving. Can drive over 40 min without any check engine light turning on. No codes come up, while clearly having issues. After a day of being off, car goes back to normal without those issues, just vibrations and pulsing on idle. -happens on Texas highways where vehicle begins to have troubl…”
NHTSA complaint #11652167, 2023
Suspension 2 1 crash 1 injury
“The contact leased a 2021 Audi A4. The contact stated that the dealer had provided her with the vehicle rental while her vehicle was being repaired. The contact stated that while driving at 4 MPH and turning into a parking pace on the 4th floor of a parking garage, the vehicle inadvertently accelerated on its own at 100 MPH. The contact depressed the brake pedal several times but it failed to respond. The vehicle crashed into the fence of steel and broke a portion of the wall. The air bags deployed. There were no warning lights illuminated. The contact sustained two concussions and a heart att…”
NHTSA complaint #11440644, 2021 · crash · 1 injury(ies)
“The contact owns a 2021 Audi A4. The contact received notification of NHTSA campaign number: 21V295000 (Suspension) however, the part to do the recall repair was unavailable. The vehicle was taken to the local dealer who stated that the parts were not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.”
NHTSA complaint #11425403, 2021
Vehicle Speed Control 2 2 crash 1 injury
“The contact leased a 2021 Audi A4. The contact stated that the dealer had provided her with the vehicle rental while her vehicle was being repaired. The contact stated that while driving at 4 MPH and turning into a parking pace on the 4th floor of a parking garage, the vehicle inadvertently accelerated on its own at 100 MPH. The contact depressed the brake pedal several times but it failed to respond. The vehicle crashed into the fence of steel and broke a portion of the wall. The air bags deployed. There were no warning lights illuminated. The contact sustained two concussions and a heart att…”
NHTSA complaint #11440644, 2021 · crash · 1 injury(ies)
“The contact owned a 2021 Audi A4. The contact stated that while driving at a low rate of speed through a parking lot, the vehicle independently accelerated and the brake pedal locked. The vehicle accelerated up a hill as the contact was unable to depress the brake pedal; he collided with an electric pole which caused the vehicle to stop. Due to the shock and abruptness of the failure, the contact was uncertain if any warning lights illuminated the instrument panel. The air bags did not deploy upon impact. The contact and no other bystanders were injured as a result of the failure. The police a…”
NHTSA complaint #11418441, 2021 · crash
Air Bags 1 1 crash
“The contact owned a 2021 Audi A4. The contact stated that while driving at a low rate of speed through a parking lot, the vehicle independently accelerated and the brake pedal locked. The vehicle accelerated up a hill as the contact was unable to depress the brake pedal; he collided with an electric pole which caused the vehicle to stop. Due to the shock and abruptness of the failure, the contact was uncertain if any warning lights illuminated the instrument panel. The air bags did not deploy upon impact. The contact and no other bystanders were injured as a result of the failure. The police a…”
NHTSA complaint #11418441, 2021 · crash
Engine 1
“The vehicle at 13,xxx miles on the high ways, and during stop & go traffic; vehicle begins to tremble, transmission and floor shakes, rpms are higher than normal, abnormal noises coming from engine (screeching), jerking on acceleration on the first gears, rough idle, happens only on highways after 1hr of driving. Can drive over 40 min without any check engine light turning on. No codes come up, while clearly having issues. After a day of being off, car goes back to normal without those issues, just vibrations and pulsing on idle. -happens on Texas highways where vehicle begins to have troubl…”
NHTSA complaint #11652167, 2023
Tires 1
“Tires are original equipment. Only 19,000 miles on them. Was told all 4 tires have belt shifts and hop some. Suggested they should be replaced. These tires were great when new but you could tell from driving they were degrading. I'm [XXX] and never had an issue with tires this new. The belt shifting could be a manufacturing issue or hitting to many potholes. I suspect it is a combination of the two. Tire size is 245/40R18. Looking at internet reviews, these tires are great but wear out very prematurely. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B…”
NHTSA complaint #11684155, 2025
How we read this (methodology)
How to read this: raw complaint totals are not a clean reliability score — a model year with more cars sold, or simply more years on the road, accumulates more complaints regardless of how good it is. So this page leans on two signals that are not distorted by sales volume: the share of complaints falling on each vehicle system (the breakdown above) and NHTSA's own crash / fire / injury / death flags. When we compare model years of the same model, we normalise by years on the road (complaints ÷ vehicle age) rather than comparing raw totals. Age-normalised, the 2021 Audi A4 draws about 1.8 complaints per year on the road, ranking 10 of 11 among the Audi A4 model years we have ingested (1 = most complaints per year on road).
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Related
Data source: U.S. NHTSA (nhtsa.gov). SaveVIN surfaces public recall data and is not affiliated with or endorsed by NHTSA.