Model year guide

2021 Audi A4

Recalls, most-reported problems, crash-test ratings, fuel economy and what a 2021 Audi A4 is worth — from official NHTSA and EPA data. 337 on record.

2021 Audi A4 — representative photo
Representative photo

2021 Audi A4 at a glance

Safety recalls4
Owner complaints11
Overall safety5 / 5 ★

Included: that car's specs and build sheet, model-year recall campaigns and a fair price.

2021 Audi A4 recalls 4

Back Over Prevention:display Function NHTSA Campaign #22V742000 · manufacturer #91DZ · 05/10/2022

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 t…

Fix: 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.

Tires NHTSA Campaign #22V034000 · manufacturer #42L5 · 26/01/2022

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 af…

Fix: 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.

Seat Belts NHTSA Campaign #21V606000 · manufacturer #69CR, 69CS · 05/08/2021

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 Se…

Fix: 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 r…

Suspension:rear:axle:non-powered Axle Assembly NHTSA Campaign #21V295000 · manufacturer #42L1 · 26/04/2021

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 …

Fix: 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.

Source: U.S. NHTSA, checked 4 Nov 2026. A campaign covers the model year; to see whether a particular car still needs the repair, check its VIN on NHTSA.gov or ask a franchised dealer.

2021 Audi A4 common problems

The most-reported problem areas across all 11 owner complaints filed with NHTSA — and what to check before you buy.

Electrical System
Test every electrical feature: windows, locks, infotainment, charging and all lights. Watch for flickering, dead accessories or warning lights.
Power Train
Drive through every gear: watch for slipping, hard or delayed shifts, and shudder. Check for transmission/driveline leaks and noises.
Lane Departure
Have a trusted mechanic inspect this system as part of a pre-purchase inspection.
Forward Collision Avoidance
Have a trusted mechanic inspect this system as part of a pre-purchase inspection.
Suspension
Listen for clunks over bumps, check the car sits level, and look for uneven tire wear and worn shocks or struts.
Vehicle Speed Control
Test cruise control and throttle response, and watch for any hesitation or unintended acceleration.

2021 Audi A4 safety ratings

Overall★★★★★
Frontal crash★★★★★
Side crash★★★★★
Rollover★★★★★
Frontal — driver★★★★★
Frontal — passenger★★★★★
Side — front seat★★★★★
Side — rear seat★★★★★
Side pole★★★★★

Rollover risk: 9.9% — NHTSA's estimated chance of rollover in a single-vehicle crash (dynamic test: ).

Source: NHTSA 5-Star Safety Ratings (NCAP), tested as the 2021 Audi A4 4 DR AWD. Ratings can differ by body style and drivetrain.

Dimensions & weight

Length
187.4 in
Width
72.8 in
Height
56.3–59.1 in
Wheelbase
111.0 in
Curb weight
3,633–3,854 lb
Front track
61.8–62.2 in
Rear track
61.0–61.8 in

Manufacturer-reported figures for the 2021 Audi A4 — ranges cover the 2 body / drivetrain versions on record. Source: Transport Canada vehicle specifications via NHTSA.

Investigations & service bulletins

Manufacturer service bulletins 1057

Technical notes the manufacturer sent to dealers about known issues and fixes. Useful to mention to a mechanic — they are not recalls and repairs may not be covered. Showing the 10 most recent of 1057.

This bulletin provides information for reporting safety related information to the manufacturer.

Bulletin TSB_2052680_2 · Sep 2026

This bulletin provides information when the starter/generator drive belt is noisy or came off.

Bulletin TSB_2083393_1 · Engine · Sep 2026

This bulletin states that technicians are required to report to the manufacturer when a vehicle has flooded, and specify the height to which the vehicle has been flooded.

Bulletin TSB_2083409_1 · Sep 2026

This bulletin provides service information regarding exterior glass cleaning.

Bulletin TSB_2020552_15 · Visibility/wiper · Sep 2026

This bulletin provides informaiton when DTC B200FF0 is stored.

Bulletin TSB_2065871_4 · Steering · Sep 2026

This bulletin provides information about vibrations and rotational steering vibrations.

Bulletin TSB_2074846_5 · Steering · Sep 2026

This bulletin provides information when the rear parking sensor sometimes does not work, rear parking sensor loose, rear parking sensor fault message.

Bulletin TSB_2068573_6 · Electrical System · Sep 2026

This bulletin provides information about billing for a broken sunroof glass panel.

Bulletin TSB_2078648_4 · Structure · Sep 2026

This bulletin provides information when the license plate mounting bracket threded inserts are stripped.

Bulletin TSB_2030471_9 · Sep 2026

This bulletin provides information when there are stails/marks on the sill panel trim.

Bulletin TSB_2073860_2 · Structure · Sep 2026

Source: NHTSA Office of Defects Investigation, listed for the A4 AWD. Model-year data, not specific to one car.

Canadian recalls 4

Transport Canada recall campaigns for the 2021 Audi A4. Relevant if the car was first sold in, or imported from, Canada.

Visual System

Issue: On certain vehicles, a software problem could cause the rearview camera image not to appear on the display. Canadian regulations require the rearview image to display when the transmission is shifted into reverse gear. Safety Risk: A rearview camera image that does not display could reduce a driver's ability to see behind the vehicle while backing up. This could increase…

Transport Canada #2022565 · Oct 2022

Suspension

Issue: On certain vehicles, the rear wheel alignment was not checked during recall 42L1 (Transport Canada Recall 2021-249). As a result, the steering could pull to one side or another and the tires could wear unevenly. If you continue to drive the vehicle in this condition, there may be reduced traction. Eventually, a tire could fail and lose air pressure. Safety Risk: A tire f…

Transport Canada #2022022 · Jan 2022

Seats And Restraints

Issue: On certain vehicles, the passenger seat belt assemblies may contain defective automatic locking retractors (ALR). As a result, the seat belts may not properly lock to secure a child seat. Safety Risk: A seat belt that is used to secure a child restraint but is not properly locked could increase the risk of injury in a crash. Corrective Actions: Audi will notify owners by…

Transport Canada #2021486 · Aug 2021

Suspension

Issue: On certain vehicles, the lock nuts for the rear trailing arm bolts may be defective. If a nut breaks, there could be sudden changes in rear wheel alignment. This can cause a loss of vehicle stability. Safety Risk: Reduced vehicle stability could cause a loss of control and increase the risk of a crash. Corrective Actions: Audi will notify owners by mail and instruct you…

Transport Canada #2021249 · Apr 2021

Source: Transport Canada Motor Vehicle Safety Recalls Database.

About the Audi A4

The Audi A4 is a line of luxury compact executive cars produced from 1994 to 2025 by the German car manufacturer Audi, a subsidiary of the Volkswagen Group. The A4 has been built in five generations and is based on the Volkswagen Group B platform. The first generation A4 succeeded the Audi 80. The automaker's internal numbering treats the A4 as a continuation of the Audi 80 lineage, with the initial A4 designated as the B5-series, followed by the B6, B7, B8, and the B9.

From Wikipedia, licensed CC BY-SA 4.0. Describes the model line in general, not this model year specifically.

2021 Audi A4 vehicles on record

Other Audi A4 model years

2021 Audi A4 — frequently asked questions

Does the 2021 Audi A4 have any safety recalls?

NHTSA lists 4 recall campaigns for the 2021 Audi A4. Whether an individual car still needs a recall repair depends on its VIN — check it on NHTSA.gov or ask a franchised dealer. Recall repairs are done at no charge.

What are the most common problems with the 2021 Audi A4?

Across all 11 owner complaints filed with NHTSA, the most-reported problem areas are electrical system, power train, lane departure.

What is the 2021 Audi A4 safety rating?

NHTSA gives the 2021 Audi A4 an overall crash-test rating of 5 out of 5 stars (frontal 4★, side 5★, rollover 5★).

Sources: NHTSA (recalls, complaints, crash tests), U.S. EPA (fuel economy). Vehicle data only — CarLogs never shows owner information.