Overview

A frequent sight on UK roads, and a regular visitor into the UK Top 10 bestsellers list when new, the W205 generation of Mercedes-Benz C-Class saloon was sold between 2014 and 2021.

A popular used car now, it looks good, has excellent safety kit for the period, a luxurious interior and the draw of the three-pointed star prominent on the grille. But does that mean it’s worth your attention?

Mercedes C-Class W205 common faults and problems

You’d expect a Mercedes to be a premium product with bank-vault build quality. But this C-Class never faired particularly well in customer satisfaction surveys when new, and was subject to quite a number of official recalls during its lifetime. Things did improve with age, so you can expect later models to be better made than the earliest examples – but it doesn’t take a genius to work out that these will be more expensive, too.

Popular rivals include the BMW 3 Series and Audi A4 – as well as less obviously default choices, such as the Jaguar XE and Alfa Romeo Giulia. Below we’ve listed 10 of the most common problem areas to keep in mind when shopping for a used C-Class W205.

Buying guide

Common issues, and what to look for if you’re thinking of getting one

1. Emission control problems – especially on diesels

Regardless of brand, recent diesel engines always have the potential to be problematic, especially as the years pile on. The desire to make them as clean as possible have made them very complex, and they don’t take well to be driven short distances. On the W205 C-Class you need to look out for problems with the diesel particulate filter (DPF), the NOx sensors and the AdBlue system.

2. Suspension problems

A lot of these C-Classes were fitted with air-suspension – which is great for ride comfort, not so great for keeping maintenance bills down as they get older. A whole host of things can go wrong with this system, and you’ll probably need a specialist to fix it. Look for warning lights, any sense that the ride isn’t as smooth, and if at all possible, swing by the location of the car you’re planning to buy and see if it’s sitting properly the day before your test drive.

While we’re on the subject of suspension, this C-Class can be rather heavy on its lower front control arms. Check the front tyres for uneven wear and make sure it drives straight with no vibrations.

3. Interior quality

The W205 has a reputation for splitting its seat covers and suffering with baggy roof lining (headlining) – which rather undermines the luxury vibe. The interiors also have a reputation for being a bit creaky, so make sure you listen carefully when testing the car to ensure you’re happy with the noises it makes. After all, if you buy it, you’ll have to live with it.

4. Electronics

Lots of electrical bits inside this C-Class. And some of them weren’t very reliable right from the start – CD players, the touchpad that controls the infotainment, the centre console switches, all of these and more can be problematic. The chances are that any issues will have already been resolved, but check everything inside works. Everything. Then check it again.

5. Cooling system

Keep an eye on the water temperature display when you’re trying the car. There are a lot of plastic parts in the cooling system that can fail with age – a UV light might help you spot leaks around the engine bay, but access isn’t generous so don’t rely on this.

Those access issues are also problematic when it comes to replacing thermostats, which are a little too prone to failure on some engine variants of the W205 C-Class. Not an expensive part, but the labour can be crippling.

6. Does the car smell of petrol?

If the C200 model C-Class you’re looking at smells of petrol, it’s probably one of the fuel lines from the fuel pump. It’s usually worse when cold, so be wary of any prospective purchase that’s been warmed up prior to your arrival.

Not actually a very big deal, once sorted – just make sure it’s reflected in the asking price.

7. Other engine issues

There are a few other things to look out for under the bonnet. Plastic air inlets also crack with age, the crank-case ventilation valves are a weak point – though usually flagged by a warning message on the dashboard – the camshaft position sensors can go out of whack and, rarely, turbos can fail.

If the car doesn’t idle or run smoothly, if could be one of these issues. Turbo problems will be indicated by a lack of power, compensated by extra smoke. Drive a few examples of the model you’re after if you can, to be sure you know what the performance should be like.

8. Power-steering problems

This C-Class has had numerous power-steering issues reported over its lifetime, including multiple recalls. The steering should be smooth from lock to lock and free from vibration or unusual noises.

9. Automatic gearboxes

Most of these C-Classes sold in the UK were fitted with automatic gearboxes. Take a long enough test drive that you’re able to fully sample how it behaves in every gear and at a complete range of speeds. Any sign of inconsistent behaviour either walk away or make sure the car is priced to account for remedial work.

10. Plug-in hybrids

Don’t worry – there’s not a major problem with these that means you should automatically avoid them. But they are complex, and heavy, which means they can be hard on tyres and if you aren’t able to plug them in to recharge on a regular basis you’re probably better off with a conventional model.

They have been known to have problems with starter motors, but when not running right the first thing to check is that the software is fully up to date. A lot of owners complained that the got nowhere near the claimed electric-only mileage when new, and used examples are likely to be worse.

What models and trims can you buy?

The W205 C-Class came with a wide choice of petrol and diesel engines – including the aforementioned plug-in hybrids – and a spread of trim levels intended to make it attractive to budget-but-image-conscious shoppers as well as those seeking baby Mercedes S-Class levels of luxury. A midlife facelift in 2018 was subtle but extensive.

AMG Line models were especially popular, but beware the large wheels and firm ride that goes with them. Air suspension is worth seeking out for the added sophistication it brings, but do make sure it’s working properly. C-Class Estate and C-Class Coupe variants of this car were also offered, but we’ve covered them separately.

Over the next few pages, we’ll review each aspect of the W205 C-Class, taking into account its practicality, comfort, fuel economy and performance. If you’re short on time, you can also skip to our verdict page to see if we recommend this Mercedes as a good used car.