2021 AUDI A4

If you've been searching for a 2021 Audi A4 S Line 45 TFSI Premium Plus Sedan for sale in Middleton, WI, this listing at Middleton Auto Mart deserves a close look. With its sport-tuned S Line trim, powerful turbocharged mild-hybrid engine, and Audi's legendary Quattro AWD system, this A4 delivers a premium driving experience at a used-car price point that makes genuine sense for Wisconsin buyers.

About This 2021 Audi A4 S Line 45 TFSI Premium Plus

This 2021 Audi A4 carries 136,146 miles, which puts it squarely in the high-mileage category — but context matters here. The A4 platform, particularly the post-2017 B9 generation, is engineered to go the distance when properly maintained. Audi's 2.0-liter turbocharged engine is known for its durability in real-world conditions, and many A4 owners report 200,000-plus miles with routine upkeep. At this mileage, the heavy depreciation has already occurred, meaning you're getting a fully loaded Premium Plus trim with S Line sport aesthetics for a fraction of what it cost new. If you're a buyer who values German engineering, a refined interior, and all-weather AWD capability without the new-car sticker shock, this A4 checks the right boxes.

2021 Audi A4 Performance and Engine

Turbocharged Mild-Hybrid Power

Under the hood sits Audi's 2.0-liter four-cylinder turbocharged engine paired with a mild-hybrid system — what Audi calls MHEV technology. This setup doesn't make the A4 a plug-in hybrid, but the 48-volt mild-hybrid system assists during acceleration and enables smoother engine restarts, contributing to improved fuel efficiency and reduced drivetrain strain. Real-world fuel economy typically lands in the 27–34 MPG range depending on driving conditions.
 

7-Speed S Tronic Dual-Clutch Transmission

Paired to the engine is Audi's 7-speed S Tronic dual-clutch automatic — one of the most responsive transmissions in the segment. It delivers near-instantaneous gear changes that feel both sporty and smooth, whether you're merging onto the Beltline or cruising through Dane County backroads. Combined with Quattro AWD, this drivetrain handles Wisconsin winters with confidence.

Audi A4 S Line Features and Interior

The S Line trim brings visual and functional upgrades over the standard A4, including sport-tuned suspension, S Line exterior badging, and a more aggressive front fascia. The Premium Plus package adds layers of technology and comfort that elevate everyday driving significantly.

Expect features typical of the 2021 A4 Premium Plus configuration, including Audi's Virtual Cockpit digital instrument cluster, a MMI touch display infotainment system, dual-zone automatic climate control, heated front seats, power-adjustable front seats, Audi pre sense safety suite, and Bang and Olufsen or standard premium audio depending on configuration. The interior uses high-quality materials throughout — soft-touch surfaces, available leather upholstery, and meticulous German fit-and-finish that still feels premium well into six-figure mileage.

Audi A4 Reliability and Ownership

The B9-generation A4 (2017–2023) is widely regarded as one of the more reliable Audi platforms in recent memory. Consumer Reports and owner forums consistently highlight the 2.0T engine's durability, and the S Tronic dual-clutch transmission has a strong track record when serviced at proper intervals. Common ownership considerations at higher mileage include oil consumption monitoring, DSG fluid service, and inspection of the PCV system — all routine for German turbocharged engines.

Maintenance costs are higher than a domestic sedan, but significantly less than you might expect from a luxury brand if you use a qualified independent Audi specialist alongside dealer service intervals. Parts availability is excellent, and the A4's widespread ownership means there's no shortage of knowledgeable technicians in the Dane County area.

Why Buy From Middleton Auto Mart in Middleton, WI

Middleton Auto Mart is a locally trusted dealership serving buyers throughout Middleton and the greater Dane County area. As an independent dealer, Middleton Auto Mart offers the flexibility that large franchise stores often can't — straightforward pricing, a no-pressure sales process, and the ability to work with buyers across a wide range of credit situations.

Situated in Middleton in Dane County, the dealership is conveniently accessible for buyers coming from across the region. Whether you're making the short drive from the west side or coming in from farther out in Dane County, this A4 is worth the trip.

Financing a Used Audi A4 Near Middleton

Financing a higher-mileage luxury vehicle is very manageable when you work with a dealer that has the right lending relationships. Middleton Auto Mart works with multiple lenders to find competitive rates for buyers across the credit spectrum — from excellent credit to buyers still rebuilding. A higher-mileage vehicle like this A4 can also mean a lower loan principal, which translates to more manageable monthly payments without stretching your term unnecessarily.

To get started, you can call Middleton Auto Mart at 608-826-2886 or inquire online. Having a few recent pay stubs and a trade-in value estimate ready will help speed up the process.

Frequently Asked Questions

Is the 2021 Audi A4 a good buy at high mileage?

Yes — when properly inspected and maintained, the 2021 A4 is a strong high-mileage buy. The B9 platform is mechanically sound, and many owners drive well past 150,000–200,000 miles with regular oil changes and scheduled service. A pre-purchase inspection by an Audi-familiar technician is always recommended.
 

What does the S Line 45 TFSI trim include?

The S Line package adds sport-tuned suspension, S Line exterior styling elements, and interior sport accents. The 45 TFSI designation indicates the 2.0-liter turbocharged engine producing approximately 261 horsepower. The Premium Plus package builds on the base Premium with added technology, comfort features, and driver assistance systems.
 

How does Audi Quattro AWD perform in Wisconsin winters?

Quattro AWD is among the most respected all-wheel drive systems in the industry. For Wisconsin winters — including the heavy snow and ice conditions common in Dane County — it provides excellent traction and stability. Paired with a good set of winter tires, the A4 Quattro is genuinely capable in cold-weather driving.
 

What is the fuel economy on a 2021 Audi A4 45 TFSI?

The 2021 A4 45 TFSI with MHEV technology is EPA-rated at approximately 27 MPG city and 34 MPG highway. Real-world numbers vary depending on driving habits, but the mild-hybrid system meaningfully improves efficiency compared to earlier A4 models.
 

How many miles is too many for a used Audi A4?

There's no hard cutoff, but buyers should focus more on service history and condition than mileage alone. A well-maintained A4 at 136,000 miles in documented good condition often outperforms a neglected example at 60,000. Always request service records and consider an independent inspection.

Serving Middleton and Surrounding Areas

Middleton Auto Mart serves buyers throughout Dane County and beyond. Whether you're coming from Waunakee, Sun Prairie, Verona, Fitchburg, Stoughton, or the surrounding communities of western and central Dane County, the dealership is easy to reach and worth the drive for a vehicle like this 2021 Audi A4.

Dane County's growing population of professional buyers, university-affiliated households, and tech-sector commuters makes it one of Wisconsin's strongest markets for refined, capable used vehicles — and this A4 fits squarely into that demand.

Contact Middleton Auto Mart Today

Ready to get behind the wheel of this 2021 Audi A4 S Line 45 TFSI Premium Plus? Contact Middleton Auto Mart in Middleton, Wisconsin today to schedule a test drive. Call us at 608-826-2886, reference stock number 00908700, and one of our team members will have this A4 ready for you. Don't wait — well-priced Audi inventory at this trim level moves quickly, and this one won't last long on the lot.