Verdict
2021 Audi S4: Complaints, Recalls & Known Issues
What the public record actually says about the 2021 Audi S4 — every figure below is a NHTSA or EPA number, not an opinion.
The read
Fewer reported complaints than most sedan.
Owners filed 2 NHTSA complaints — fewer complaints than 90% of 2021 sedans. Electrical System leads the reports (50%). 4 safety recall campaigns on record — check the VIN and remedy terms with a dealer.
Based on NHTSA complaint volume against 2021 sedans, not adjusted for how many were sold. It describes the model year, not the individual car you are looking at.
Complaints filed
2
Reports to NHTSA, 2021
Safety recalls
4
NHTSA campaigns on record
NHTSA crash test
Not rated
Overall NCAP rating
Combined MPG
23
EPA estimate
Complaint volume vs. segment peers
Fewer complaints than 90% of 2021 sedans
The bar is this car's percentile among 2021 sedans by complaint volume — a full bar means the fewest complaints in its class. Not adjusted for sales.
Known issues
Electrical System issues lead owner complaints (50% of 2 reports), followed by unknown or other (50%).
Share of all 2 NHTSA complaints for this model year, grouped by the component owners named. Bars are scaled to the largest category. Examples: ODI 11689741.
Recalls(4)
Open a recall to read what NHTSA says is wrong, what can happen, and how it gets fixed. Check the VIN and remedy eligibility with a dealer; federal no-charge requirements have an age limit, though a manufacturer may offer more coverage.
Back Over PreventionMay 2022 · 22V742000Details +Close −
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."
Risk: 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.
Seat BeltsMay 2021 · 21V606000Details +Close −
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."
Risk: 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).
Suspension · 21V295000Details +Close −
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.
Risk: 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.
Tires · 22V034000Details +Close −
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.
Risk: 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.
A campaign can apply to this model year without being incomplete on a specific vehicle. Check the VIN with NHTSA or a dealer to confirm whether a particular car needs repair.
Investigations
0 NHTSA investigations on record
No investigations are on record as of Jul 2026. An empty record is not a clean bill of health.
Crash-test ratings
2021 Audi S4 4 DR AWD NHTSA source
- Overall
- Not rated
- Frontal
- Not rated
- Side
- Not rated
- Rollover
Fuel economy by trim
| Trim | Engine | Drivetrain | Transmission | City | Hwy | Combined |
|---|---|---|---|---|---|---|
| S4 | 3.0L 6-cyl | All-Wheel Drive | Automatic (S8) | 20 | 28 | 23 |
EPA laboratory estimates by trim and engine. Actual mileage varies with driving, weather, load, and maintenance. EPA source.
Before you buy
Useful next checks
Federal records tell you about patterns. These checks can tell you more about the specific car in front of you.
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Compare model years
"Fewest reports" and "most complained" describe raw NHTSA complaint totals, not vehicle reliability. The last few model years are left unlabelled because they have had less road time.
2021 Audi S4: frequently asked
What does the complaint record show for the 2021 Audi S4?
Owners filed 2 NHTSA complaints about the 2021 Audi S4 — fewer complaints than 90% of comparable 2021 sedans, so it sits toward the stronger end of its class. That's a signal, not a guarantee about any single car.
What are the most common problems on the 2021 Audi S4?
The most-reported problem areas are Electrical System (50% of complaints) and unknown or other (50%).
How many recalls does the 2021 Audi S4 have?
4 recalls have been issued that affect the 2021 Audi S4, covering components such as back over prevention. Check the VIN with NHTSA and ask a dealer to confirm remedy eligibility; federal no-charge requirements have an age limit, though manufacturers may offer more coverage.
What gas mileage does the 2021 Audi S4 get?
The EPA rates the 2021 Audi S4 at 23 mpg combined.