YearToAvoid

2021 Audi S4 Problems, Recalls & Reliability

Verdict

No verdict

Complaint Index

30/100

#8 most-complained of 11 S4 years

The 2021 Audi S4 has a complaint index of 30, ranking 8th worst out of 11 model years for this model. NHTSA lists 2 complaints and 4 recalls, with no crashes, fires, injuries, or deaths reported.

Complaints
2
Recalls
4
Crashes / fires
0 / 0
Injuries / deaths
0 / 0
NHTSA overall rating
Not rated
EPA combined MPG
23
20 city / 28 hwy

Top 2021 Audi S4 problems

NHTSA owner complaints by component group. Groups with 15+ complaints have their own page.

  1. Electrical System1 (50%)
  2. Other1 (50%)

What owners report

  • Vehicle loses power suddenly while driving, with no warning before the shutdown.
  • Check engine light illuminates at the same time as the power loss.
  • Dashboard displays a "Drive System Malfunction - Please Contact Service" message.
  • After the malfunction, the vehicle has trouble restarting and shifting into gear.
  • This failure was reported at 31,000 miles on the odometer.
2021 Audi S4 complaints: complaints filed per month1Jan 2023Sep 2025
2 complaints filed with NHTSA from Jan 2023 to Sep 2025; peak Jan 2023 (1).

2021 Audi S4 recalls

4 NHTSA recall campaigns list this model year.

  1. NHTSA 22V742000Oct 5, 2022Collision Avoidance & Cameras170,296 vehicles

    Back over prevention:display function

    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.

  2. NHTSA 22V034000Jan 26, 2022Suspension, Wheels & Tires31,058 vehicles

    Tires

    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.

  3. NHTSA 21V606000Aug 5, 2021Seat Belts45,496 vehicles

    Seat belts:rear/other:retractor

    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).

See all 4 recalls for the 2021 Audi S4 →

2021 Audi S4 fuel economy and fuel cost

City
20 MPG
Highway
28 MPG
Combined
23 MPG
Annual fuel cost (EPA)
$3,450
15,000 mi/yr
Fuel
Premium
Current regular gas
$4.32/gal
national avg.

EPA figures; median across configurations of this model year. Estimate your own cost with the fuel cost calculator.

2021 compared with other S4 years

Complaint Index by model year (0 = fewest issues, 100 = most)025507510020102011201220132014201520182019202020212022
Complaint Index: 0 = fewest issues, 100 = most, relative to other years of this model. Avoid Caution Good Best
YearVerdictIndexComplaintsRecallsMPG
2019No verdict202124
2020Caution6016323
2021No verdict302423
2022No verdict101124

All Audi S4 years: best and worst →

Frequently asked questions

Is the 2021 Audi S4 reliable?
NHTSA data shows a complaint index of 30 for the 2021 Audi S4, ranking 8th worst among the 11 model years with data, which is better than most other S4 years.
What problems does the 2021 Audi S4 have?
The top reported problem area is the Electrical System, including a case of sudden power loss with a "Drive System Malfunction" warning at 31,000 miles. NHTSA lists 2 total complaints for this year.
Does the 2021 Audi S4 have any recalls?
Yes, NHTSA lists 4 recalls for the 2021 Audi S4, covering collision avoidance/camera software, suspension lock nuts, seat belts, and rear axle/tire wear inspection. None are do-not-drive recalls.
How does the 2021 Audi S4 compare to other S4 years?
With a complaint index of 30, the 2021 S4 ranks 8th worst out of 11 years tracked, well below the 2010 model year's index of 100, the highest among all years listed.
What is the fuel economy of the 2021 Audi S4?
EPA rates the 2021 Audi S4 at 23 mpg combined (20 city / 28 highway), with an estimated annual fuel cost of $3,450.

Sources: NHTSA Office of Defects Investigation complaint and recall databases; U.S. EPA fuel economy data; NHTSA 5-Star Safety Ratings. Complaints are unverified owner reports.

Data updated Sep 24, 2026. Read the methodology and data sources. The Complaint Index is based on NHTSA owner complaints and recalls; it is not a reliability rating.