【Review】2021 Audi A4 Review: A Used Car Buyer's Guide (Price, Reliability & Specs)

2021 Audi A4 Model Overview & B9 Generation

The 2021 model year brought substantial improvements to Audi’s compact luxury sedan, positioning it strongly against BMW and Mercedes-Benz competitors in the pre-owned market. Understanding these changes helps buyers recognize the value proposition this specific year offers.

2021 Audi A4 B9 Generation Review

The B9 generation, introduced in 2017, reached new maturity in 2021 with significant technology and powertrain updates. According to J.D. Power, the 2021 A4 achieved a quality and reliability rating of 75/100, placing it solidly in the average category for luxury sedans^[1].

This generation resolved the notorious oil consumption issues that plagued the earlier B8 generation (pre-2017 models). The EA888 Gen 3B engine architecture underwent refinements that eliminated most mechanical weaknesses found in earlier iterations.

Autvex experts note that the B9’s longitudinal engine layout provides superior weight distribution compared to competitors’ transverse setups, contributing to the A4’s balanced handling characteristics that became even more refined in 2021.

What’s New for 2021 Audi A4

The 2021 model year brought three major improvements that transformed the A4’s value equation. Most significantly, Quattro all-wheel drive became standard across all trim levels, previously a $2,100 option^[2].

The addition of a 12-volt mild-hybrid system boosted both engine options by 13 horsepower while improving fuel economy and refinement. This system uses a belt-driven starter-generator to provide seamless stop-start operation and mild regenerative braking.

Technology upgrades included wireless Apple CarPlay as standard equipment, lane departure warning across all trims, and an enhanced MMI infotainment system with faster processing. The 10.1-inch touchscreen replaced the previous rotary controller, modernizing the interface.

Is the 2021 Audi A4 a Good Used Car

Based on comprehensive reliability data and owner satisfaction scores, the 2021 A4 represents solid value in the used luxury segment. J.D. Power’s driving experience rating of 76/100 indicates owners appreciate the vehicle’s design, comfort, and technology^[1].

The combination of standard all-wheel drive, proven powertrains, and comprehensive technology makes it particularly appealing. Original MSRPs ranged from $39,100 to $52,000, while current used prices of $20,000-$28,000 represent significant depreciation that benefits second owners.

However, buyers should factor in higher maintenance costs compared to mainstream brands. Annual maintenance averages $900-$1,100, though this remains competitive within the luxury segment. If you’re wondering how many miles can Audi last, properly maintained A4s routinely exceed 150,000 miles.

2021 A4 vs 2020 A4

The 2021 model received substantial improvements over 2020, making it the more desirable choice for used car buyers. The mild-hybrid system’s addition alone justifies the typical $1,000-$2,000 price premium in the used market^[2].

Key differences include the 13-horsepower boost from mild-hybrid assistance, wireless smartphone connectivity becoming standard, and Quattro all-wheel drive no longer requiring additional payment. The 2020 model lacked these features unless optioned accordingly.

Technology improvements extended to the MMI system’s responsiveness, with 2021 models featuring updated software that resolved many glitches present in 2020 versions. This makes 2021 the sweet spot for reliability and features.

2021 A4 vs 2022 A4

Comparing to the following year reveals minimal changes, making 2021 models exceptional value. The 2022 model year brought only minor updates including new paint colors and slight equipment shuffling^[3].

Performance specifications remained identical between years, with the same engine options and output figures. Technology features stayed consistent, with both years offering the same infotainment capabilities.

The primary difference lies in pricing—2022 models command approximately $2,000-$3,000 premium in the used market for essentially the same vehicle. This makes 2021 the value leader for budget-conscious luxury buyers.

2021 Audi A4 S Line

The S Line package transformed the A4’s appearance without the S4’s price premium. External enhancements included more aggressive bumpers, side skirts, and exclusive wheel designs ranging from 18 to 19 inches^[2].

Interior upgrades featured sport seats with improved bolstering, brushed aluminum trim, and a three-spoke flat-bottom steering wheel. The package also included a sport-tuned suspension lowering ride height by 0.9 inches.

While improving handling response, some owners found the sport suspension too firm for daily comfort. The trade-off between sporty dynamics and ride quality should be carefully considered during test drives.

Engine Performance & Drivetrain Specifications

The 2021 A4 offered two versions of Audi’s proven turbocharged four-cylinder engine, both enhanced by the new mild-hybrid system that improved performance and efficiency.

2021 Audi A4 40 TFSI Horsepower

The base 40 TFSI produces 201 horsepower and 236 lb-ft of torque, representing a 13-horsepower increase over 2020 thanks to mild-hybrid assistance. This output proves adequate for most driving situations while maximizing fuel efficiency^[2].

Peak torque arrives at just 1,450 rpm, providing strong low-end response for city driving and highway merging. The seven-speed S-tronic dual-clutch transmission delivers crisp shifts, though some drivers note occasional low-speed hesitation.

Real-world performance feels stronger than numbers suggest, with the mild-hybrid system filling torque gaps during gear changes. The combination creates smooth, refined power delivery suitable for luxury sedan expectations.

2021 Audi A4 45 TFSI Horsepower

The upgraded 45 TFSI generates 261 horsepower and 273 lb-ft of torque, transforming the A4 from competent to genuinely quick. This engine shares its architecture with various Volkswagen Group performance models^[2].

The 60-horsepower advantage over the base engine becomes most apparent during highway passing and spirited driving. Torque delivery remains linear throughout the rev range, avoiding the peaky nature of some turbocharged competitors.

S Line models with the 45 TFSI include a sport-tuned suspension as standard equipment. This combination appeals to drivers seeking performance without stepping up to the more expensive S4.

2021 Audi A4 2.0T Engine

Both variants utilize the EA888 Gen 3B engine, renowned for reliability after years of refinement. The 2.0-liter displacement features direct injection, turbocharging, and variable valve timing for optimal efficiency and performance^[3].

The addition of the 12-volt mild-hybrid system uses a belt-driven starter-generator replacing the traditional alternator. This provides up to 13 horsepower of electrical assistance during acceleration while enabling seamless engine stop-start operation.

Premium fuel is recommended for optimal performance, though regular unleaded won’t cause damage. Using premium typically improves fuel economy by 1-2 mpg while providing slightly better throttle response.

2021 A4 40 vs 45 TFSI Review

Choosing between variants depends on individual priorities and driving style. The 40 TFSI suits buyers prioritizing fuel economy and lower purchase price, saving approximately $3,000-$4,000 in the used market.

The 45 TFSI justifies its premium through significantly improved acceleration and passing power. Insurance costs increase by roughly $150-$200 annually, though this remains reasonable for the performance gain.

Test driving both variants reveals distinct personalities—the 40 TFSI feels refined and adequate, while the 45 TFSI delivers genuine enthusiasm. Urban drivers may find the base engine sufficient, while highway commuters appreciate the extra power.

2021 A4 0-60 Time

Acceleration figures demonstrate the meaningful performance gap between variants. The 40 TFSI reaches 60 mph in approximately 5.5 seconds, respectable for a luxury sedan prioritizing comfort^[2].

The 45 TFSI significantly improves to 4.8-5.2 seconds, placing it among the quickest in its segment. Launch control, standard on both variants, optimizes acceleration from standstill.

Real-world performance often matches published figures thanks to the Quattro system’s excellent traction. The all-wheel drive eliminates wheel spin common in rear-drive competitors, providing consistent acceleration regardless of conditions.

2021 Audi A4 Standard Quattro

Making Quattro all-wheel drive standard represents the 2021 model’s most significant improvement. This system provides superior traction in adverse conditions while enhancing dry-weather handling dynamics^[1].

The system typically sends 60% of power to the rear wheels under normal conditions, creating a rear-biased feel. During slip detection, power distribution adjusts instantly to maintain traction.

Fuel economy impact remains minimal, with only 1-2 mpg penalty versus theoretical front-wheel drive. The benefits in snow, rain, and emergency maneuvers far outweigh this minor efficiency loss. Understanding what does Quattro in Audi mean helps appreciate this engineering advantage.

2021 Audi A4 12-volt Mild-Hybrid System

The mild-hybrid system represents thoughtful engineering that improves both performance and efficiency without complexity. Unlike full hybrids, this system cannot power the vehicle independently but provides meaningful benefits^[3].

During deceleration, the system recovers energy through regenerative braking, storing it in a compact lithium-ion battery. This energy assists acceleration, reducing engine load and fuel consumption.

The most noticeable improvement comes from refined stop-start operation. The belt-driven starter-generator restarts the engine almost imperceptibly, eliminating the jarring sensation common in traditional systems.

2021 A4 MPG

Fuel economy impresses for a luxury all-wheel-drive sedan. The 40 TFSI achieves 25 mpg city and 34 mpg highway, while the more powerful 45 TFSI manages 24/31 mpg^[2].

Real-world testing by various outlets confirms these figures are achievable with normal driving. Highway cruising at 70 mph typically returns 35-36 mpg in the 40 TFSI thanks to tall gearing and aerodynamic efficiency.

The mild-hybrid system contributes approximately 2-3 mpg improvement through regenerative braking and engine-off coasting. Combined with the standard auto stop-start, urban fuel consumption improves significantly versus non-hybrid predecessors.

Reliability Issues & Common Problems

Understanding potential issues helps buyers make informed decisions and budget appropriately for maintenance. The 2021 A4’s reliability story proves largely positive with specific areas requiring attention.

2021 Audi A4 Reliability

J.D. Power awarded the 2021 A4 an overall rating of 76/100, with quality and reliability specifically scoring 75/100. This places it in the average category for luxury vehicles, neither exceptional nor concerning^[1].

Consumer Reports predicted reliability data aligns with J.D. Power findings, suggesting consistent ownership experiences. The mature B9 platform and proven powertrains contribute to this stability.

Owner forums report high satisfaction with mechanical reliability, with most issues involving electronics rather than drivetrain components. This pattern typical of modern luxury vehicles with complex technology systems.

2021 Audi A4 Common Problems

While generally reliable, several issues appear consistently in owner reports and service records. The most prevalent concern involves MMI infotainment system freezes requiring system resets or software updates.

The Audi Pre-Sense safety system occasionally triggers false warnings, particularly in parking situations or near construction zones. Dealer software updates typically resolve these calibration issues.

Some owners report vibrations through the chassis at specific speeds, often traced to the all-wheel-drive system’s clutch pack. Technical Service Bulletins address this issue with updated calibration or component replacement under warranty.

2021 Audi A4 Recalls

Three significant recalls affect 2021 A4 models, with the most widespread being the rearview camera display issue. NHTSA recall 22V-742 addresses software errors preventing camera display when shifting to reverse, affecting 170,296 Audi vehicles^[4].

The rear axle alignment recall (21V-295) involves potential stress corrosion of lock nuts, requiring inspection and possible replacement. This safety-critical issue demands immediate attention if unresolved.

A smaller recall addresses seat belt pretensioner concerns in specific production batches. Dealers can verify recall completion status instantly through VIN lookup during pre-purchase inspections.

2021 Audi A4 Infotainment Screen Frozen

MMI system freezes represent the most common owner complaint, occurring randomly but typically resolving through simple resets. Holding the volume button for 10-15 seconds forces a system restart^[1].

Persistent freezing often indicates corrupted software requiring dealer intervention. Updates are typically covered under warranty or performed as goodwill repairs outside warranty period.

Prevention involves keeping the system updated and avoiding interruption during software installations. Using quality USB cables for smartphone connections also reduces glitch frequency.

2021 Audi A4 MMI Problems

Beyond freezing, the MMI system occasionally exhibits connectivity issues with smartphones, particularly Android Auto. Wireless connections may drop intermittently, requiring wired backup connections.

Navigation system updates require dealer visits or complicated download procedures. Unlike some competitors offering over-the-air updates, Audi’s system remains traditional in this aspect.

Voice recognition accuracy varies, with some accents or commands poorly understood. The system learns over time but never matches smartphone assistant capabilities. For those interested in technology costs, understanding does Audi charge for Apple CarPlay helps budget for features.

2021 Audi A4 Audi Pre-Sense Problems

The Pre-Sense safety system occasionally triggers unnecessary emergency braking or warnings. Construction zones with concrete barriers commonly cause false positives^[2].

Calibration sensitivity can be adjusted through dealer programming, reducing nuisance activations while maintaining safety effectiveness. Some owners choose to temporarily disable the system in problematic areas.

Despite occasional false triggers, the system provides genuine safety benefits. IIHS testing awarded top ratings for the A4’s collision avoidance capabilities, validating the technology’s value.

2021 A4 AWD Clutch System Vibration

A subset of vehicles experience vibrations between 35-45 mph, traced to the Quattro system’s center differential clutch pack. Technical Service Bulletins guide dealers through diagnosis and repair procedures.

The issue typically manifests as a subtle shuddering sensation during light acceleration. While not safety-critical, it affects refinement expected in luxury vehicles.

Warranty coverage typically addresses this issue at no cost. Outside warranty, repairs range $800-$1,500 depending on component replacement requirements.

B9 Generation Reliability

The B9 generation’s overall reliability trajectory shows steady improvement since 2017 introduction. Early production issues with thermostat housings and water pumps were resolved by 2019^[3].

Transmission reliability stands out positively, with the S-tronic dual-clutch proving robust when maintained properly. DSG fluid changes every 40,000 miles ensure longevity.

Long-term durability data suggests B9 models achieve 150,000+ miles with proper maintenance. The platform’s maturity by 2021 provides confidence for used car buyers seeking reliability.

Interior Features & Technology

The A4’s cabin represents a highlight, combining premium materials with intuitive technology that remains competitive despite the model’s age.

2021 Audi A4 Interior Review

Interior quality immediately impresses with soft-touch surfaces covering most contact points. Even base Premium trim includes genuine leather seating and authentic aluminum or wood trim options^[2].

Build quality feels exceptional with no squeaks or rattles reported even after 50,000 miles. Panel gaps remain tight and consistent, reflecting Audi’s reputation for interior excellence.

Ergonomics excel with controls logically arranged and easily accessed. The driver-centric design angles the center stack slightly toward the operator, improving usability while driving. Autvex notes this attention to detail distinguishes Audi from competitors.

2021 Audi A4 Virtual Cockpit

Available on Premium Plus and Prestige trims, the 12.3-inch Virtual Cockpit transforms the driving experience. This fully digital instrument cluster offers multiple display modes including full-screen navigation^[3].

Customization options let drivers prioritize information display. Sport mode emphasizes the central tachometer with digital speed readout, while efficiency mode highlights fuel economy data.

Google Earth integration provides satellite navigation imagery directly in the gauge cluster. This feature particularly impresses passengers and adds genuine navigation utility in unfamiliar areas.

2021 A4 10.1-inch Touchscreen

The 10.1-inch MMI touchscreen runs Audi’s latest MIB 3 infotainment platform, offering crisp graphics and generally responsive operation. Haptic feedback provides confirmation of inputs without looking away from the road^[2].

Wireless Apple CarPlay and Android Auto eliminate cable clutter while maintaining full smartphone integration. The wireless connection generally maintains stability, though some users keep cables for backup.

Natural voice commands understand conversational language like “I’m cold” to adjust climate control. The system learns preferences over time, suggesting frequently used functions.

2021 A4 Wireless Apple CarPlay

Standard wireless Apple CarPlay represents significant convenience improvement over previous years requiring wired connections. Initial pairing takes under a minute with automatic reconnection thereafter^[1].

Connection stability generally impresses, though concrete parking structures or areas with heavy wireless interference occasionally cause drops. A USB cable provides reliable backup when needed.

The system supports full Siri integration, allowing voice control of navigation, messaging, and music without touching the screen. This enhances safety while maintaining connectivity.

2021 A4 Cargo Space

Trunk capacity measures 12 cubic feet, average for the compact luxury sedan segment. The wide opening and low liftover height facilitate loading, though the opening itself could be larger^[3].

Rear seats fold in a 40/20/40 configuration, providing flexibility for longer items while maintaining passenger space. The center pass-through accommodates skis or lumber without folding entire seatbacks.

Interior storage disappoints slightly with a small center console and limited door pockets. The wireless charging pad, when equipped, reduces console storage further. Considering how long does it take to buy a car, factor in testing storage adequacy for your needs.

High-Performance Variants

Understanding available performance options helps buyers decide whether the standard A4 meets their needs or if stepping up makes sense.

2021 Audi S4 Review

The S4 significantly elevates performance with a turbocharged 3.0-liter V6 producing 349 horsepower and 369 lb-ft of torque. This represents a substantial upgrade from even the 45 TFSI A4^[5].

Zero to 60 mph acceleration drops to just 4.4 seconds, placing the S4 firmly in sports sedan territory. The V6’s linear power delivery feels more refined than the four-cylinder’s somewhat peaky nature.

Used S4 pricing ranges $35,000-$45,000, representing approximately $10,000 premium over comparable A4s. Insurance and maintenance costs also increase proportionally.

2021 Audi S4 3.0T V6

The 3.0-liter turbocharged V6 represents traditional Audi engineering excellence. Single turbo configuration provides immediate response while maintaining reliability superior to previous supercharged versions^[5].

Torque delivery impresses from idle to redline, with massive mid-range punch ideal for highway passing. The engine note, while muted in Comfort mode, provides satisfying growl in Dynamic settings.

Fuel economy suffers compared to four-cylinder models, averaging 20/27 mpg city/highway. However, performance enthusiasts consider this acceptable given the performance gains.

2021 Audi S4 0-60

Published acceleration of 4.4 seconds to 60 mph proves consistently achievable thanks to launch control and standard Quattro traction. Quarter-mile passes in 12.9 seconds at 105 mph^[5].

More importantly, in-gear acceleration from 50-70 mph takes just 3.2 seconds, demonstrating the V6’s superior passing power. This real-world performance distinguishes S4 from upgraded A4 variants.

The eight-speed automatic transmission contributes to performance with quicker shifts than the A4’s seven-speed dual-clutch. Paradoxically, the traditional automatic proves smoother in daily driving.

Used 2021 Audi S4 Review

As used purchases, S4 models offer compelling performance value having depreciated similarly to A4 variants. Original MSRPs exceeded $55,000, while current values range $35,000-$45,000.

Reliability remains strong with the proven V6 architecture. However, maintenance costs increase approximately 30% over four-cylinder models, particularly for brake and tire replacement.

The S4 appeals to enthusiasts wanting genuine performance without S6 or RS model pricing. For family duties, the subtle styling maintains practicality while delivering sports car acceleration.

2021 Audi A4 Allroad Review

The A4 Allroad provides an interesting alternative, raising ride height 1.3 inches and adding rugged body cladding. This variant appeals to buyers wanting mild off-road capability without full SUV commitment^[3].

Standard roof rails and increased ground clearance suit outdoor enthusiasts. The wagon body style provides 29.1 cubic feet of cargo space, significantly exceeding the sedan’s capacity.

Used Allroad models command slight premiums over equivalent sedans, typically $1,000-$2,000 more. The added versatility justifies this cost for buyers needing extra cargo flexibility.

Used Market Pricing & Value Analysis

Understanding current market dynamics and depreciation patterns helps buyers recognize good deals and negotiate effectively.

Used 2021 Audi A4 Price

Current market analysis shows 2021 A4s trading between $20,000-$28,000 depending on trim, mileage, and condition. This represents significant depreciation from original MSRPs of $39,100-$52,000^[1].

Trim Level	Average Used Price	Original MSRP
40 TFSI Premium	$20,000-$22,000	$39,100
40 TFSI Premium Plus	$23,000-$24,000	$43,900
40 TFSI Prestige	$26,000-$27,000	$48,900
45 TFSI Premium S Line	$21,000-$24,000	$42,700
45 TFSI Premium Plus S Line	$24,000-$25,000	$46,500
45 TFSI Prestige S Line	$27,000-$28,000	$51,500

Geographic variations affect pricing, with California and Northeast markets commanding 10-15% premiums versus Southern states.

2021 Audi A4 Value 2025

After four years, 2021 A4 models have experienced approximately 45-50% depreciation, typical for luxury sedans. This steep initial depreciation creates excellent value for second owners^[6].

Depreciation rates are now stabilizing at 5-8% annually going forward. Well-maintained examples with complete service histories hold value better than average.

The combination of significant depreciation, proven reliability, and comprehensive features makes 2021 models particularly attractive in 2025’s used market.

Original MSRP 2021 Audi A4

Understanding original pricing helps evaluate current values. Base Premium trim started at $39,100, with Premium Plus at $43,900 and Prestige reaching $48,900^[2].

Popular options included the Convenience Package ($1,400), Black Optic Package ($1,000), and Bang & Olufsen sound system ($950). Fully equipped examples approached $54,000.

Comparing current prices to original MSRPs reveals exceptional value, particularly for higher trim levels that depreciated more dramatically.

Is the 2021 Audi A4 Worth It

Value analysis strongly supports 2021 A4 purchases for buyers seeking luxury features, all-wheel drive, and modern technology at accessible prices. The combination of depreciation and reliability creates compelling value^[1].

Certified Pre-Owned examples command $2,000-$3,000 premiums but include extended warranties and thorough reconditioning. This coverage often justifies additional cost for risk-averse buyers.

Alternative considerations include Genesis G70 for warranty coverage or the 2024 BMW 3 Series for sportier dynamics. However, the A4’s standard Quattro and mild-hybrid efficiency provide unique advantages.

2021 A4 Depreciation

Depreciation patterns follow predictable luxury sedan trajectories. First-year depreciation hit hardest at approximately 20%, moderating to 10-12% annually through year three^[6].

Current four-year-old examples have depreciated 45-50% from new, representing the sweet spot where dramatic initial depreciation has passed while maintaining modern features and remaining warranty coverage.

Future depreciation should moderate to 5-8% annually, making current purchases relatively stable investments. Well-maintained examples with complete records depreciate slowest.

Competitor Comparisons

Comparing the A4 against primary rivals clarifies its market position and helps identify the best choice for individual priorities.

2021 Audi A4 vs 2021 BMW 3 Series

BMW’s 3 Series remains the segment’s dynamic benchmark, offering superior steering feel and chassis balance. The 330i’s turbocharged four-cylinder matches the 45 TFSI’s output while delivering more engaging driving characteristics^[3].

However, BMW charges extra for features standard on the A4, including all-wheel drive ($2,000) and many technology features. Comparably equipped 3 Series models cost $3,000-$5,000 more used.

Reliability data slightly favors the A4, though both score acceptably. The BMW’s sportier nature appeals to driving enthusiasts, while the Audi provides better value and all-weather capability. When comparing SUV alternatives, explore Audi Q5 vs BMW X3 differences.

2021 Audi A4 vs 2021 Mercedes-Benz C-Class

Mercedes-Benz completely redesigned the C-Class for 2022, making 2021 the final year of the previous generation. This older design shows its age against the A4’s more modern technology^[3].

The C300’s turbocharged four-cylinder produces 255 horsepower, splitting the difference between A4 variants. However, all-wheel drive remained optional, adding cost and complexity.

Interior quality favors Mercedes with more opulent materials, though technology falls behind Audi’s Virtual Cockpit and wireless connectivity. Used pricing runs similar to A4, making the choice largely preference-based.

2021 Audi A4 vs 2021 Genesis G70

Genesis offers compelling value with the G70, providing similar luxury and performance at lower prices. The 2.0T model matches the 45 TFSI’s acceleration while undercutting A4 pricing by $3,000-$5,000 used^[3].

The G70’s aggressive styling and sport-focused dynamics appeal to younger buyers. However, Genesis’ limited dealer network complicates service and reduces convenience compared to Audi’s established infrastructure.

Genesis’ 10-year/100,000-mile warranty impresses, though it doesn’t transfer to second owners. The A4’s proven long-term reliability and superior dealer support may justify its premium for many buyers.

Key Takeaways

Standard Quattro AWD and mild-hybrid system distinguish 2021 from earlier years
J.D. Power reliability score of 76/100 places it average for luxury sedans
Two engine choices (201hp or 261hp) suit different performance priorities
Used pricing of $20,000-$28,000 represents 45-50% depreciation from new
Verify recall completion for rearview camera and rear axle issues
Wireless CarPlay and Android Auto come standard on all trims
Annual maintenance costs $900-$1,100 align with luxury segment norms

Next Steps

Begin your search by determining whether the 40 or 45 TFSI best suits your driving style and budget. The base engine provides adequate performance with superior fuel economy, while the 45 TFSI delivers genuine enthusiasm for roughly $3,000 more.

Obtain a pre-purchase inspection from an Audi specialist or dealer, budgeting $200-$300 for comprehensive evaluation. Request service records documenting regular oil changes and the 40,000-mile DSG service if applicable.

Verify recall completion through NHTSA’s website using the specific VIN. The rearview camera and rear axle recalls are safety-critical and should be addressed before purchase. Dealers complete recalls free regardless of warranty status.

Test the infotainment system thoroughly during test drives, checking for freezing, connectivity issues, and touchscreen responsiveness. While software updates resolve most issues, persistent problems may indicate hardware failures.

Compare Certified Pre-Owned versus private party options carefully. CPO vehicles cost more but include warranty extensions and thorough inspections that may offset the premium through reduced repair risk.

Research insurance costs before finalizing your purchase. The A4’s standard safety features often qualify for discounts, though luxury classification increases base rates. Budget approximately $1,400-$1,800 annually for coverage.

Consider extended warranty options if purchasing outside factory coverage. Audi’s complex electronics make coverage worthwhile, particularly for MMI and Virtual Cockpit components. Third-party warranties often provide better value than dealer offerings.

Finally, evaluate your long-term ownership plans. The 2021 A4’s combination of features, reliability, and current depreciation makes it ideal for 3-5 year ownership periods. According to Autvex analysis, this model year represents peak value in the B9 generation, offering maximum features at accessible prices.

FAQs

What are the common problems with the 2021 Audi A4?

Common issues include frozen MMI infotainment screens, buggy Audi Pre-Sense system, AWD clutch vibration (TSB), and occasional technology lag with kick-to-open trunk feature.

Is the 2021 Audi A4 a reliable car to buy used?

Yes, with J.D. Power rating it 76/100 for overall quality and reliability (average for luxury segment), though maintenance costs are higher than non-luxury cars.

Was Quattro all-wheel drive standard on the 2021 A4?

Yes, Quattro became standard on all 2021 A4 models in the US, a significant change from previous years when it was a $2,100 option.

What is the difference between the 2021 A4 40 and 45 TFSI?

The 40 TFSI produces 201hp and 236 lb-ft torque, while 45 TFSI delivers 261hp and 273 lb-ft, with 0-60 times of 5.5 vs 4.8-5.2 seconds.

What is the horsepower of the 2021 Audi A4?

The 2021 A4 offers either 201 horsepower (40 TFSI) or 261 horsepower (45 TFSI), both with 12-volt mild-hybrid assistance adding 13hp.

What is the difference between the 2021 A4 and the 2020 A4?

The 2021 added a 12-volt mild-hybrid system (+13hp), made Quattro AWD standard, and included wireless Apple CarPlay as standard equipment.

How much does a used 2021 Audi A4 cost in 2025?

Used 2021 A4s range from $20,000-$22,000 (40 TFSI Premium) to $27,000-$28,000 (45 TFSI Prestige S Line) depending on trim and condition.

Were there any recalls on the 2021 Audi A4?

Yes, including rear axle lock nut stress corrosion and rearview camera software issues (NHTSA 22V-742) causing blank display—verify completion before purchasing.

How much horsepower does the 2021 Audi S4 have?

The 2021 Audi S4 produces 349 horsepower from its 3.0-liter turbocharged V6 engine, significantly more than the A4’s offerings.

Is the 2021 Audi A4 worth buying in 2025?

Yes, offering excellent value with standard AWD, mild-hybrid efficiency, and strong tech features at depreciated prices of $20,000-$28,000.

How does the 2021 A4 compare to the 2021 BMW 3 Series?

The A4 offers standard AWD and better value, while the 3 Series provides sportier handling but charges extra for AWD and similar features.

References

J.D. Power. (2025). 2021 Audi A4 Reliability, Consumer Ratings & Pricing. https://www.jdpower.com/cars/2021/audi/a4
U.S. News & World Report. (2023). 2021 Audi A4 Review, Pricing, & Pictures. https://cars.usnews.com/cars-trucks/audi/a4/2021
Car and Driver. (2021). 2021 Audi A4 Review, Pricing, and Specs. https://www.caranddriver.com/audi/a4-2021
NHTSA. (2022). Audi Recall 22V-742: Rearview Camera Display Issue. https://www.cars.com/research/audi-a4-2021/recalls/
Audi USA. (2021). 2021 Audi Model Specifications. https://www.audiusa.com
Kelley Blue Book. (2025). 2021 Audi A4 Values and Pricing. https://www.kbb.com/audi/a4/2021/

Chien Nguyen Van

I am a senior automotive analyst at Autvex. Expert vehicle evaluations, in-depth reviews, and objective analysis helping readers make informed automotive decisions with years of industry experience.