Model years Mercedes-Benz C-Class
2018 Mercedes-Benz C-Class
This year drew an ordinary 254 complaints for a Mercedes-Benz C-Class — the model's median is 280. What they were about is the unusual part: 26% of them mention valve, against 4.2% across the model's other years.
NHTSA opened a defect investigation into this model year.
| Complaints filed | 254 |
|---|---|
| Median for this model | 280 |
| Involving a crash | 10 |
| Recalls | 0 |
| NHTSA crash rating | 5/5 |
| EPA combined | 25 mpg |
What the complaints were about
- valve — 26% of this year's complaints, against 4.2% across the model's other years (6.1×). Owners wrote it as: valve, ventilation, crankcase ventilation, ventilation valve.
- water — 18.9% of this year's complaints, against 5.6% across the model's other years (3.4×). Owners wrote it as: water, under recall, manager, correctly.
- appeared — 7.9% of this year's complaints, against 2.8% across the model's other years (2.8×). Owners wrote it as: appeared, transmission failed, vehicle only, rearview.
Words owners used for the same problem are counted together, so a fault written four different ways is measured once. Grouped by which complaints they appear in, not by a list anyone wrote in advance.
What owners wrote
My c300 2018 only has 50k and suddenly the engine light is on, when I check it shows that I need the Positive Crankcase ventilation valve replaced. it cost $2300. As I know a lot of people who own Mercedes have the same problem. Three mechanics claim it on alm…
My Mercedes C300 2018 only have 33k miles on it, but I was leaking oil and gas from the positive crankcase ventilation valve which is not environment friendly. As I know many other who own Mercedes also have the same problem.
Verbatim from NHTSA complaint filings, with identifying details removed.
How this was worked out
Every year of the Mercedes-Benz C-Class was compared against its own history rather than against other cars, which removes popularity and age from the answer — a common car draws more complaints at equal reliability, and an older one has had longer to accumulate them. A year is flagged when it drew at least 2.5× this model's median and at least 50 complaints.
This is a fault record, not a review. Nobody files a federal complaint to say the car was fine, so it shows what tends to go wrong — not whether owners liked it, and not whether it is a good car.
Source: NHTSA complaints, recalls and investigations, retrieved . Look this vehicle up directly on NHTSA's site to check anything here.
Own a 2018 Mercedes-Benz C-Class? What happened to yours?
Loading comments…