2021 Audi S4: complaints, problems and recalls
Explore the records behind recurring owner reports.
Key facts
2 owner complaints analyzed
4 distinct recall campaigns
31,000 mi median reported failure mileage
Scope: 2021 model year. Data snapshot: . 1 complaints include usable failure mileage.
Most common problems
Electrical System is the most frequently named component, appearing in 1 of 2 complaints (50.0%). A complaint can name multiple components.
| Topic | Matching reports | Share of complaints |
|---|---|---|
| Transmission and shifting | 1 | 50.0% |
Topic matches use published keyword rules. They describe mentions, including negations or comparisons, and do not confirm a diagnosis. Read the matching rules.
Component breakdown
Number of unique complaints naming each component. Top eight shown.
| Category | Count |
|---|---|
| Electrical System | 1 |
| Unknown Or Other | 1 |
Electrical System: 1; Unknown Or Other: 1
Reported problems by failure mileage
Complaint counts in mileage bands. These are not failure rates per vehicle or mile.
| Category | Count |
|---|---|
| Under 25,000 | 0 |
| 25,000 to 49,999 | 1 |
| 50,000 to 74,999 | 0 |
| 75,000 to 99,999 | 0 |
| 100,000 to 149,999 | 0 |
| 150,000 and above | 0 |
Under 25,000: 0; 25,000 to 49,999: 1; 50,000 to 74,999: 0; 75,000 to 99,999: 0; 100,000 to 149,999: 0; 150,000 and above: 0
25,000 to 49,999 miles has the most reports with usable mileage (1). 1 complaints have missing, zero or invalid mileage.
Complaints over time
Year the complaint was filed, not the vehicle model year or incident year. The snapshot year is partial.
| Category | Count |
|---|---|
| 2023 | 1 |
| 2025 | 1 |
2023: 1; 2025: 1
Pattern summary
Electrical System leads the component reports. Transmission and shifting appears in 1 complaint narratives. Use these patterns to inspect individual reports and prepare questions for a mechanic.
Calculated from recorded counts. An AI narrative has not been published for this selection.
Examples from the source records
Examples provide context, not a representative sample or a verified diagnosis.
Owner report 11504613 · 2023-01-31 (January 31, 2023)
2021 AUDI S4. CONSUMER WRITES IN REGARD TO NHTSA SAFETY RECALL 22V-742. THE CONSUMER IS DISGUSTED AND DISATISFIED WITH THE AUDI SERVICE DEPARTMENT PROCEDURES FOR PERFORMING THE RECALLS.
Owner-reported narrative. Look up ODI 11504613 at NHTSA ↗
Owner report 11689741 · 2025-09-25 (September 25, 2025)
The contact owns a 2021 Audi S4. The contact stated that while driving at an undisclosed speed, the vehicle experienced a loss of automotive power. The check engine warning light was illuminated. The message "Drive System Malfunction - Please Contact Service" was displayed. In addition, the vehicle hesitated to restart and shift into gear as intended. The contact stated that the failure had progressed over time. The vehicle was taken to a local dealer, where it was diagnosed with needing a pending software service update; however, the repairs w…
Owner-reported narrative. 31,000 miles reported. Look up ODI 11689741 at NHTSA ↗
Recall history
4 distinct campaigns affect this selection. Announcement dates below are different from vehicle model years. A campaign may cover multiple years.
21V295000 · Suspension:Rear:Axle:Non-Powered Axle Assembly
Reported: 2021-04-26 (April 26, 2021)
Volkswagen Group of America, Inc. (Audi) is recalling certain 2021 Q7, Q8, Q5 Sportback, SQ5 Sportback, RS6 Avant, RS7, RS Q8, 2020-2021 Audi S6 sedan, Q5, A8, S8, A7, A6 Allroad, A5 Cabriolet, A4 sedan, A4 Allroad, SQ5, S7, A6 sedan, S5 coupe, S4 sedan, S5 Cabriolet, A5 coupe, 2019-2021 RS5 coupe, A5 Sportback, S5 Sportback, RS5 Sportback vehicles. The lock nut on the trailing arm of the rear axle may break due to stress corrosion.
Consequence: A broken lock nut may misalign the rear axle, causing a loss of control and increasing the risk of a crash.
Remedy: Dealers will replace the lock nuts and, if necessary, the associated bolts, free of charge. Owner notification letters were mailed June 4, 2021. Owners may contact Audi customer service at 1-800-253-2834. Audi's number for this recall is 42L1.
NHTSA campaign record ↗21V606000 · Seat Belts:Rear/Other:Retractor | Seat Belts
Reported: 2021-08-05 (August 5, 2021)
Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2021 Volkswagen ID4, Audi A4 Allroad, A4 Sedan, A5 Cabriolet, A5 Coupe, A5 Sportback, A6 Allroad, A6 Sedan, A7, A8, E-Tron Quattro, E-Tron Sportback Quattro, Q3, Q5, Q5 Sportback, Q7, Q8, RS5 Sportback, RS5 Coupe, RS6 Avant, RS7, RSQ8, S4 Sedan, S5 Cabriolet, S5 Coupe, S5 Sportback, S6 Sedan, S7, S8, SQ5, SQ5 Sportback, SQ7, SQ8, and 2021-2022 S3 Sedan vehicles. The rear seat belt automatic locking retractors may deactivate early, which can prevent the child restraint system from securing properly. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."
Consequence: An unsecured child restraint system can increase the risk of injury during a crash.
Remedy: Dealers will inspect, and replace as necessary, the middle-rear seat belt assemblies, free of charge. Owner notification letters were mailed August 27, 2021. Owners may contact Volkswagen customer service at 1-800-893-5298 and Audi customer service at 1-800-253-2834. Volkswagen's numbers for this recall are 69CR (VW) and 69CS (Audi).
NHTSA campaign record ↗22V034000 · Tires | Suspension:Rear:Axle:Non-Powered Axle Assembly
Reported: 2022-01-26 (January 26, 2022)
Volkswagen Group of America, Inc. (Audi) is recalling certain 2019-2021 Audi A5 Sportback, RS5 Coupe, RS5 Sportback, S5 Sportback, 2020-2021 A4 Allroad, A4 Sedan, A5 Cabriolet, A5 Coupe, A6 Allroad, A6 Sedan, A7, A8, Q5, S4 Sedan, S5 Coupe, S5 Cabriolet, S6 Sedan, S7, S8, SQ5, 2021 Q5 Sportback, Q7, Q8, RS6 Avant, RS7, RSQ8, SQ5 Sportback, SQ7, and SQ8 vehicles. The rear axle alignment may not have been inspected after the repairs for Recall 21V-295 (42L1) were performed.
Consequence: Rear axle misalignment may cause premature or uneven tire wear, increasing the risk of a crash.
Remedy: Dealers will inspect the rear axle, adjust the alignment as necessary, and replace any prematurely or unevenly worn tires, free of charge. Owner notification letters were mailed March 3, 2022. Owners may contact Audi customer service at 1-800-253-2834. Audi's number for this recall is 42L5.
NHTSA campaign record ↗22V742000 · Back Over Prevention:Display Function
Reported: 2022-10-05 (October 5, 2022)
Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2021 Audi A8, RS7, RS6 Avant, RS5 Sportback, RS5 Coupe, Q8, Q7, Q5 Sportback, S4 Sedan, Q5, A7, A6, A6 Allroad, A5 Sportback, A5 Coupe, A5 Cabrioleet, A4 Sedan, A4 Allroad, E-Tron Sportback Quattro, SQ7, S5 Cabriolet, E-Tron Quattro, SQ8, SQ5 Sportback, SQ5, S8, S7, S6 Sedan, S5 Sportback, S5 Coupe, 2022 E-Tron GT, and 2021-2022 RSQ8 vehicles. Due to a software issue, a blank or black screen may be displayed instead of the rearview camera image when the vehicle is placed in reverse gear. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."
Consequence: A blank rearview camera display can reduce the driver's rear visibility, increasing the risk of a crash.
Remedy: Dealers will update the infotainment unit software, free of charge. Owner notification letters were mailed October 25, 2022. Owners may contact Audi's customer service at 1-800-253-2834. Volkswagen's number for this recall is 91DZ.
NHTSA campaign record ↗