What are the most common Mercedes-Benz C-Class problems?

According to Au7o's analysis of 1,500+ owner reports, the 2021 Mercedes-Benz C-Class has 1 documented issue. The documented issue is: M274 Turbo Wastegate Rattle. None are rated critical, but regular maintenance is recommended.

Is the Mercedes-Benz C-Class reliable?

The 2021 Mercedes-Benz C-Class has 1 known issue documented across 1,500+ owner reports. No issues are rated critical, suggesting generally good reliability. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common Mercedes-Benz C-Class problems?

Repair costs for known Mercedes-Benz C-Class issues range from $400 to $2,500, depending on the specific problem and whether you choose DIY or professional repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What is the 2015-2021 Mercedes-Benz C-Class M274 Turbo Wastegate Rattle?

The M274 2.0L turbo engine develops an audible wastegate rattle at idle and low RPM due to wear in the wastegate actuator linkage. While not immediately dangerous, it worsens over time and can eventually affect boost control. Repairs typically run $400-$2,500. Severity: medium.

Mercedes-Benz · Known Issues

2021 Mercedes-Benz C-Class Problems: 1 Issue Every Owner Should Know

2021 model year · 1,500+ owner reports · Updated June 2026

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According to Au7o's analysis of 1,500+ owner reports, the 2021 Mercedes-Benz C-Class has 1 documented issue. No issues are rated critical, indicating generally reliable ownership. The most commonly reported issue is M274 Turbo Wastegate Rattle with 1,500 owner reports. Across all issues with published estimates, repair costs range from $400 to $2,500. DIY maintenance guides at au7o.io.

2021 Mercedes-Benz C-Class Problems: 1 Issue Every Owner Should Know

All 1 Known Issue

2015-2021 Mercedes-Benz C-Class: M274 Turbo Wastegate Rattle#

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Frequently Asked Questions

What are the most common Mercedes-Benz C-Class problems?

Is the Mercedes-Benz C-Class reliable?

How much does it cost to fix common Mercedes-Benz C-Class problems?

What is the 2015-2021 Mercedes-Benz C-Class M274 Turbo Wastegate Rattle?