2021 Audi S4 reliability

Is it reliable?

NHTSA's file on the 2021 Audi S4 holds 2 complaints after 6 years, a rate of 0 per year. That is more complaints per year than most S4 years here — over the median of the other years, which is 0. NHTSA has 4 recalls on file, including Display, Tires, and Retractor.

2012 Audi S4 — Photo by Autoviva, resized from the original. Wikimedia Commons CC BY 2.0

Complaints

Per year

Recalls

Years on the road

What owners report

The complaints owners file most often name Electrical system: 1 of 2.

Next to 2020 and 2022

The 2020 S4 has 16 complaints, 0 per year, and the 2022 has 0 complaints, 0 per year. The 2021 has more complaints per year than the 2020. The 2021 has more complaints per year than the 2022.

The complaint rate is complaints filed in this year’s first 3 years on the road, divided by however many of those years have passed. Recalls are a separate count. The numbers are for the US-market 2021 Audi S4. How we count. Data as of 2026-10-16.

Recalls (4)

Recall back-over prevention, display 2022-10-05 · NHTSA campaign 22V742000

Summary 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."

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.

Recall Tires 2022-01-26 · NHTSA campaign 22V034000

Summary 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.

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.

Recall seat belts, rear or other, retractor 2021-08-05 · NHTSA campaign 21V606000

Summary 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."

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).

Recall Rear non-powered axle assembly 2021-04-26 · NHTSA campaign 21V295000

Summary 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.

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.

Complaints by component (2 total)

Electrical system

Crash-flagged

Fire-flagged

Injury reports

Death reports

Complaints filed per year

Excerpts from recent NHTSA complaint filings

"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…"
Electrical system · filed 2025-09-25
"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."
Unknown or other · filed 2023-01-31

NHTSA crash ratings

Version	Overall	Front	Side	Rollover
2021 Audi S4 4 DR AWD	Not rated	Not rated	Not rated	5 stars

Stars are how this vehicle did in NHTSA crash tests. They are a safety result, separate from the complaint record. Not rated means that test was not run for this version.

Fuel economy

Trim	Engine	Transmission	Drive	City	Hwy	Combined	Annual fuel cost
S4	3L, 6-cyl	Automatic (8-speed)	All-wheel drive	20	28	23 MPG	$3450

Specs and fitment

B9 generation, 2018–present

Body styles Sedan

Oil 0W-20 (common US fills; ~7.7 qt with filter) , 7.7 qt capacity

Tire size 245/40R18 or 245/35R19 (trim-dependent)

Known issues for this generation

Recall 19V547000 covers certain 2018-2019 Audi models including S4 on overlapping B9 campaigns for a passenger frontal air bag inflator concern as listed by NHTSA. Recall 21V874000 covers certain 2017-2020 A4 Allroad and A4 Sedan models and related B9 vehicles including S4/S5 variants on that campaign for a seats concern.

Compare

Previous year 2020 Audi S4 See every Audi S4 model year →

Frequently asked questions

Is the 2021 Audi S4 reliable?

What are common problems with a 2021 Audi S4?

The complaints owners file most often name Electrical system: 1 of 2.

Is the 2021 Audi S4 more reliable than the years next to it?

The 2020 S4 has 16 complaints, 0 per year, and the 2022 has 0 complaints, 0 per year. The 2021 has more complaints per year than the 2020. The 2021 has more complaints per year than the 2022.

Has the 2021 Audi S4 been recalled?

The 2021 Audi S4 has 4 recalls on file with NHTSA. See the recalls table on this page for dates, components, and remedies.

How many complaints have owners filed about the 2021 Audi S4?

Owners have filed 2 complaints about the 2021 Audi S4 with NHTSA.

What mpg does a 2021 Audi S4 get?

EPA-rated combined fuel economy for the 2021 Audi S4 is 23 MPG. See the fuel economy table on this page for city and highway figures by engine and transmission.

What engine oil does an Audi S4 use?

B8 S4 models commonly use 5W-30/5W-40 (~7.2 qt); B9 models commonly list 0W-20 (~7.7 qt)—confirm the manual.

What tire sizes does an Audi S4 use?

OEM sizes commonly include 245/40R18 and 245/35R19 or 255/35R19 depending on generation and package.

What fuel-rail recall covers certain early S4 models?

Recall 15V019000 covers certain 2011-2012 Audi S4 models (with S5, Q7, and 2012 A6/A7) for a fuel-rail concern that can leak fuel.