Should I buy a 2017 Mercedes-Benz C-Class 2.1 Diesel Automatic W205?

Explore common problems, estimated repair costs and practical checks for the 2017 Mercedes-Benz C-Class 2.1 Diesel Automatic W205. Use this guide to help assess a used car, then unlock a personalised report for the exact vehicle you're considering.

Common problems

1Moderate Likelihood

Coolant pump vacuum leak and overheating risk

Coolant level drops, a coolant warning appears, the heater may behave oddly, or the engine runs hotter than normal.

How to check

Warm the car fully, let it idle, then drive normally while watching the temperature display and any warning messages.

Estimated Repair Cost

£900

2High Likelihood

NOx sensor and AdBlue warning faults

Engine light, AdBlue warning, emissions message, limp mode or a restart countdown despite the tank being topped up.

How to check

Switch the ignition on, read the dash carefully, then drive until fully warm.

Estimated Repair Cost

£900

3Moderate Likelihood

Automatic gearbox hesitation or harsh low-speed shifts

Delay when moving off, a thump selecting drive or reverse, or a noticeable jerk between low gears.

How to check

Pull away gently several times, creep in traffic speed, and alternate between drive and reverse with the brake held.

Estimated Repair Cost

£450

MOT Failure Rate

0%5%10%15%20%0–20,000 miles: 8.1% (950 failed / 11,662 tests)20,000–40,000 miles: 11.4% (5,923 failed / 52,135 tests)40,000–60,000 miles: 14.2% (7,271 failed / 51,037 tests)60,000–80,000 miles: 16.4% (5,365 failed / 32,702 tests)80,000–100,000 miles: 17.6% (2,842 failed / 16,168 tests)100,000–120,000 miles: 18.3% (1,232 failed / 6,737 tests)120,000–140,000 miles: 19.2% (533 failed / 2,776 tests)140,000–160,000 miles: 17.5% (201 failed / 1,147 tests)160,000–180,000 miles: 17.8% (88 failed / 493 tests)180,000–200,000 miles: 18.7% (37 failed / 198 tests)020k40k60k80k100k120k140k160k180k200kMilesFailure rate
2017 Mercedes-Benz C-Class 2.1 Diesel Automatic W205

Mercedes-Benz C-Class buying questions

Is a 2017 Mercedes-Benz C-Class worth buying?

It can be, but only if the individual car backs it up. For the 2017 Mercedes-Benz C-Class 2.1 Diesel Automatic W205, treat model-level patterns as viewing priorities and let condition, history and inspection evidence decide.

What common problems affect the Mercedes-Benz C-Class (2017)?

The problem cards above list the model-level checks for this guide. Read them as priorities for inspection and paperwork review, not proof that every example will have those faults.

What should I check before buying a Mercedes-Benz C-Class?

Look for evidence, not just assurances: MOT advisories, service history, repair invoices, warning lights, fluid leaks, tyre and brake condition, and how the car behaves on a proper test drive. And of course, look at your personalised Should I Buy This Car? report, outlining a full list of common issues in detail, a personalised road test, a plain-English explanation and a MotorIQ score.

A model guide is useful. A report on its registration is better.

The guide above gives you the model-level pattern. A personalised MotorIQ report checks the registration-specific record and turns it into an ownership view before you commit.

Or enter the vehicle manually