The 2001 Audi S4 is a compact luxury sport sedan (also sold as the S4 Avant wagon) that blends understated styling with serious turbocharged performance and all-weather quattro traction. It sits in the B5-generation S4 lineup (2000–2002 in the U.S.), positioned as a faster, more driver-focused alternative to the A4 and a direct rival to sport sedans from BMW and Mercedes of the same era. Ideal buyers are enthusiasts who want a tunable, torque-rich daily driver with premium comfort, and who don’t mind staying on top of maintenance. In today’s market, it’s a high-value performance pick, but long-term satisfaction depends heavily on service history.

- 2.7-liter twin-turbocharged V6 (known as the 2.7T), factory-rated around 250 hp and 258 lb-ft, delivering strong midrange pull and excellent tuning potential. - quattro all-wheel drive for confident traction in rain and snow, plus a planted feel at speed. - Available 6-speed manual for maximum engagement (an automatic was also offered in many markets; most enthusiasts seek the manual). - Sport-tuned suspension and larger brakes than the A4, giving the S4 sharper handling and stronger stopping power. - Upscale interior with supportive sport seats, premium materials, and the classic early-2000s Audi cockpit layout that still feels driver-centric.

Shoppers researching “2001 Audi S4 problems,” “2001 Audi S4 reliability,” and “2001 Audi S4 common issues” will find a consistent theme: the car can be durable when maintained, but neglected examples get expensive quickly. - Turbocharger wear/failure: The stock K03 turbos are a known weak point, especially on higher-mileage or modified cars. Many owners report smoking, loss of boost, or whining turbos anywhere from roughly 80,000–130,000 miles, with earlier failures possible if oil changes were skipped or the car was frequently run hard without proper warm-up/cool-down. - Control arms and front suspension clunks: The multi-link front suspension can develop play in control arm bushings/ball joints, often showing up as clunks over bumps, wandering alignment, and uneven tire wear around 70,000–120,000 miles. - Cooling system and oil leaks: Aging rubber and plastic components can lead to coolant leaks (hoses, expansion tank, and related fittings) and oil leaks from valve cover gaskets, cam seals, or other gaskets as mileage climbs. These issues are common on 20+ year-old cars and are often “maintenance plus age” rather than a single catastrophic failure. - Ignition and sensor-related drivability issues: Misfires from coil packs or worn spark plugs, plus intermittent check engine lights from aging sensors (such as oxygen sensors or MAF-related issues) are frequently reported, typically in the 80,000–150,000-mile range depending on upkeep.