initial observation started happening intermittently a week before the car become inoperable. When the vehicle came to a stop like at a light the engine would sound like it was going to almost turn off like a rattle noise and a popping sound or like I hit a plastic bag sound on acceleration. Then the day it broke down I was merging onto interstate 15 I heard the same popping sound, the engine…
2018 Mercedes-Benz C-Class engine problems
moderate 34 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Complaints
34
Recalls
0
Avg fix
$3,100
What stands out
Owners have filed 34 engine complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
Engine accounts for 27% of all owner complaints filed against this vehicle, across 9 categories tracked.
What owners are reporting 7 most recent
When at a stop the engine will not restart sometimes. I have to start the engine manually. This has happened to me four times in 5 months .
My vehicle only had 31,000 miles and I experienced engine failure. I bought a new engine for 16, 500. 00 dollars. Mercedes Benz did nothing. I almost got in to several accidents because the engine completely stop on the interstate. Almost got hit by several cars. This is unacceptable.
My car was diagnosed with positive crankcase ventilation regulator valve performance failure. This should be recalled by the manufacturer because many c300 are having this very same issue.
Check engine light appeared.I took it to Mercedes and they said the crankshaft was faulty. I had to repair it and it cost me about $1800.00.
Engine code: P052e - the widest spread engine issue on Mercedes which fails emissions testing. Crankcase ventilator issue which leads to stalling.
Positive crank case valve failure. Check engine light on. Mechanic started this was extremely common and a costly repair on lower mileage Mercedes Benz vehicles. Mercedes Benz forums also mention this is extremely common and frustrating. This happened at slightly over 50k miles on my vehicle. Error code P052e
Had engine trouble with your 2018 Mercedes-Benz C-Class?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2018 Mercedes-Benz C-Class?
It's a documented issue but not catastrophic. 34 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Based on the 34 complaints filed, engine issues most often appear around 54,000 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2018/Mercedes-Benz/C-Class.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.