Reliability AnalysisBased on known issue patterns, repair cost data, and ownership trends · How we score

2021 Audi A4 Reliability ReportCommon Problems, Repair Costs & Expert Verdict

88/ 100

KeepScore

LOW RISK

Grade: A-

A premium daily driver that offers excellent long-term satisfaction if properly maintained.

Full system breakdown + what I would do

Quick Facts · 2021 Audi A4

  • Has 4 NHTSA recalls on record — the most notable involves the seat belts:rear/other:retractor.
  • Outscores the 2020 Audi A4 by 10 points — one of the stronger nearby years to consider.
  • The system most likely to surface first: electrical/infotainment (minor severity).

Should You Buy the 2021 Audi A4?

The 2021 Audi A4 stands as one of the most well-engineered and reliable luxury compact sedans you can buy in the used market. It perfectly blends refined performance with a high-quality interior and robust mechanicals, making it a smart choice for discerning buyers willing to invest in its premium maintenance schedule.

The 2021 Audi A4 represents a mature and highly refined iteration of a proven platform. It offers an outstanding combination of luxury, performance, and solid reliability for its class. As long as you commit to its specified maintenance schedule and budget for premium parts and labor, it will be a rewarding and depe…

Best Model Years

2018-2023 (later B9 generation models after initial kinks were addressed)

Years to Avoid

Earlier B8 generation models (pre-2012) due to more prevalent engine oil consumption and timing chain tensioner issues.

Biggest Strengths

  • Exceptional build quality and material choices
  • Refined and robust 2.0L TFSI engine (EA888 Gen 3/4 EVO)
  • Sophisticated Quattro all-wheel-drive system

Top Risk Areas

The systems that tend to fail first on the 2021 Audi A4, with the typical mileage window when each becomes a concern. Detailed repair-cost ranges and exact what-to-check inspection notes are in the full report.

1
Electrical/Infotainmentminor~20,000-70,000 mi

While generally stable, the complex MMI system and various sensors can occasionally exhibit minor glitches like screen freezing, connectivity issues, or false warning lights. These are often software-related but can sometimes require mod…

2
Cooling Systemmoderate~60,000-100,000 mi

Although improved in later EA888 generations, the integrated water pump and thermostat housing can still be a point of failure, often leading to coolant leaks. This component is plastic and prone to cracking, requiring a full assembly re…

3
Suspension Componentsmoderate~75,000-120,000 mi

Over time and especially on rough roads, various suspension bushings and control arm components can wear out, leading to clunks, squeaks, or reduced handling precision. While not a catastrophic failure, addressing these maintains the Aud…

Full repair-cost ranges, fix-before-you-buy notes, and inspection checklists are in the report.

2021 Audi A4 Mileage Danger Zones

The mileage windows when the 2021 Audi A4 most commonly needs attention. Plan ahead, budget accordingly, and inspect before you cross each threshold.

30,000

Low Risk Zone

At this mileage, the A4 is still very new. Most issues would be covered under warranty and typically involve minor electrical glitches, tire wear, or early brake pad replacement depending on driving style.

60,000

Maintenance Zone

This mileage often marks major service intervals, including spark plugs and crucially, the S-Tronic transmission fluid change. Neglecting these services can lead to long-term issues. Suspension components should be inspected.

90,000

Elevated Risk Zone

While still very capable, components like the PCV system, engine mounts, and further suspension items may begin to show wear. More significant electrical or sensor issues could arise, requiring more in-depth diagnostics.

120,000+

High Risk Zone

Beyond 120,000 miles, the A4 will likely require more proactive maintenance and potential component replacements such as significant suspension overhauls, more frequent sensor issues, and an increased (though still low) risk of transmiss…

2021 Audi A4 Ownership Cost Outlook

What it typically costs to keep the 2021 Audi A4 on the road. Full 5-year cost-of-ownership projection and major-failure-risk forecast are in the report.

Annual Maintenance

$600-900

Moderate Repairs

$700-2,000 occasionally

How Long Does the 2021 Audi A4 Last?

A well-maintained 2021 Audi A4 can reliably achieve and exceed 150,000 miles. Focus on proactive maintenance and addressing minor issues promptly to ensure long-term satisfaction.

What 2021 Audi A4 Owners Actually Say

What Owners Love

  • Exceptional interior quality and ergonomic design, feeling truly premium.
  • Refined and comfortable ride, even with sport suspension options.
  • Responsive and engaging driving dynamics with precise steering.
  • Standard Quattro AWD provides confidence in all weather conditions.

Common Frustrations

  • Rear seat legroom is somewhat cramped for taller adults on longer journeys.
  • Premium fuel requirement contributes to higher running costs.
  • Infotainment system can occasionally be finicky, requiring resets.
  • Dealer service costs are generally higher than non-luxury brands.

Who Should Buy the 2021 Audi A4?

Best For

  • Individuals seeking a refined, performance-oriented luxury compact sedan.
  • Drivers who prioritize AWD capability and a sophisticated driving experience.
  • Buyers who appreciate high-quality interiors and advanced technology.

Not Ideal For

  • Budget-conscious buyers looking for the absolute lowest cost of ownership.
  • Individuals who tend to defer or neglect routine vehicle maintenance.

How the 2021 Audi A4 Compares to Rivals

The A4 offers a compelling package, often striking a better balance between driving dynamics and overall reliability than its direct German competitors, while still delivering a true luxury experience.

More Reliable Than

  • Mercedes-Benz C-Class (reliability of infotainment and some powertrain components)
  • Alfa Romeo Giulia (overall long-term reliability and build quality)

Comparable To

  • BMW 3 Series (similar blend of performance, luxury, and maintenance costs)
  • Lexus IS (different driving dynamic, but comparable reliability with different maintenance focus)

NHTSA Recalls

4 recalls on record from NHTSA. Check your VIN atnhtsa.gov to see if the repair was performed.

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."

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.

What breaks on the 2021 Audi A4?

Full reliability breakdown — engine, transmission, rust, electrical. With repair costs and mileage danger zones.

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Audi A4 by Year

Compare KeepScores across nearby years of the Audi A4. Click any year for its full report.

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