2021 Mercedes-Benz C63 AMG S

The 2021 Mercedes-Benz C63 AMG S is a high-performance variant of the C-Class, celebrated for its powerful engine and sporty driving dynamics. It came exclusively with a handcrafted 4.0-liter twin-turbocharged V8 engine producing 503 horsepower and 516 lb-ft of torque, paired with a 9-speed automatic transmission. Owners often praise its exhilarating acceleration, aggressive styling, and luxurious interior. However, some common criticisms include its relatively stiff ride and the high running costs associated with a high-performance vehicle.

Engine

4.0L Twin-Turbo V8

• Turbocharger Failure
  • Description/Symptoms: Whining or whistling noises from the engine bay, loss of power, check engine light. The turbochargers in the C63 AMG S are known to be stressed due to high output, leading to premature failure.
  • Solution: Replace the failed turbocharger(s). It is recommended to replace both turbos at the same time to ensure balanced performance.
  • Estimated Cost to Fix: $3,000 - $6,000+
  • Recalls: None Found
• Spark Plug Failure
  • Description/Symptoms: Engine misfires, rough idling, decreased fuel economy, and a check engine light.
  • Solution: Replace the spark plugs.
  • Estimated Cost to Fix: $250 - $500+
  • Recalls: None Found

Transmission

9-Speed Automatic (AMG Speedshift MCT 9G)

• Rough Shifting/Hesitation
  • Description/Symptoms: Harsh or jerky gear changes, especially during low-speed driving. Some owners have reported hesitation when accelerating from a standstill.
  • Solution: Software reflash of the transmission control module (TCM) or valve body replacement.
  • Estimated Cost to Fix: $200 - $300+ for software, $1,500 - $3,000+ for valve body
  • Recalls: None Found

Suspension

• Air Suspension Issues (If Equipped)
  • Description/Symptoms: Vehicle sagging on one side, air compressor running constantly, “Vehicle Level Too Low” warning.
  • Solution: Replace leaking air struts or a faulty air compressor.
  • Estimated Cost to Fix: $1,500 - $3,000+ per strut, $800 - $1,500+ for compressor
  • Recalls: None Found

Electrical

• Infotainment System Glitches
  • Description/Symptoms: Freezing, lagging, or unexpected reboots of the MBUX infotainment system.
  • Solution: Software updates or replacement of the infotainment unit.
  • Estimated Cost to Fix: $0 - $300+ for software (if not under warranty), $1,500 - $3,000+ for unit replacement
  • Recalls: None Found
• Sensor Malfunctions
  • Description/Symptoms: Faulty readings from sensors (e.g., parking sensors, blind-spot monitoring), leading to warning lights and system malfunctions.
  • Solution: Diagnose the specific sensor and replace it.
  • Estimated Cost to Fix: $200 - $800+ per sensor
  • Recalls: None Found

Exterior

• No Issues Found

Interior

• Sunroof Malfunctions
  • Description/Symptoms: Sunroof getting stuck, not opening or closing properly, or making excessive noise during operation.
  • Solution: Repair or replace the sunroof motor, tracks, or assembly.
  • Estimated Cost to Fix: $500 - $2,000+
  • Recalls: None Found

Summary

The 2021 Mercedes-Benz C63 AMG S, while offering exceptional performance and luxury, does have several reported issues. The most significant relate to potential turbocharger failure and transmission roughness, which can be costly to repair. Electrical glitches in the infotainment system and sensor malfunctions are also reported. Suspension issues can occur but are less frequent. Owners should be aware of these potential problems and factor them into ownership costs. The severity ranges from minor infotainment glitches to major mechanical failures, with repair costs ranging from a few hundred dollars to several thousand, depending on the specific issue.