Check engine light came on with code P052E : Positive Crankcase Ventilation Regulator Valve Performance.
2018 Mercedes-Benz GLC-Class engine problems
severe Owners of the 2018 Mercedes-Benz GLC-Class have filed 18 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
18
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2016 GLC-Class | 28 |
| 2017 GLC-Class | 23 |
| 2018 GLC-Class (this page) | 18 |
| 2019 GLC-Class | 7 |
| 2020 GLC-Class | 17 |
| 2022 GLC-Class | 4 |
1injury
When does it fail?
Of the 18 engine complaints filed for the 2018 Mercedes-Benz GLC-Class, here's the actual mileage breakdown — failures cluster heaviest at 0-25,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
Among the 7 model years of Mercedes-Benz GLC-Class in our records for engine problems, this one ranks #3 by owner-complaint volume.
Engine accounts for 18% of all owner complaints filed against this vehicle, across 8 categories tracked.
The failure pattern owners describe
Owners consistently describe two major categories of failure. First, internal engine damage: pistons burning or breaking at very low mileage (9,200 to 55,000 miles), cylinder heads warping, and complete engine failure requiring replacement. One owner's engine was already 5,000 miles out of warranty when the piston broke. Dealers have kept vehicles for weeks while assessing the damage, and the problem remains unresolved in some cases.
Second, and far more common across the complaint set, is the positive crankcase ventilation (PCV) valve malfunction tied to diagnostic code P052E. Nearly every narrative mentioning this component identifies it as a widespread, recurring problem in 2018 GLC-Class vehicles. Owners report the valve fails multiple times within the vehicle's lifespan, and replacement at the dealership runs about $2,000 each time. Some repairs fall under warranty; others are owner-paid.
A third set of complaints involves loss of engine power and throttle response during highway driving—code P2138 points to a pedal position sensor, while one report mentions fuel pump and tank issues causing stalling in heavy traffic. These events create genuine safety hazards, with one owner describing nearly losing control at 70 mph. Owners note Mercedes has an active class action lawsuit regarding the M274 engine and appears to be disregarding the broader issue.
Same Mercedes-Benz GLC-Class engine reports on nearby years: 2016 · 2017 · 2020
Failure modes owners describe
Piston/Cylinder Damage
Burned piston rings, warped cylinder head, or complete piston failure requiring engine replacement. Owners report this as a known issue specific to the M274 engine used across multiple Mercedes models.
When: 9,200 miles; 55,000 miles
Symptoms owners cite: Hesitation under acceleration; Shaking and vibration; Check engine light illuminated; Complete loss of power; Stalling in traffic
Codes mentioned: None reported
Repairs/costs cited: Engine replacement required; one case remained unrepaired at dealer after several weeks; another case was 5,000 miles out of warranty
Recalls/TSBs owners mention: Active class action lawsuit in California regarding M274 engine failures; Mercedes reportedly ignoring the issue
Positive Crankcase Ventilation (PCV) Valve Malfunction
Crankcase breather or PCV solenoid valve failure, typically identified by code P052E. Owners consistently report this as a very common, recurring issue in the 2018 GLC-Class across multiple vehicles.
When: Under 65,000 miles; recurring within 70,000 miles
Symptoms owners cite: Check engine light illuminated; Actuator blockage; Recurring failure (multiple times per vehicle)
Codes mentioned: P052E, P052E71
Repairs/costs cited: Replacement of crankcase breather intake line (part #274-090-56-00-80 or 274090560080) costs approximately $2,000 at dealership; some covered under warranty, others owner-paid
Throttle Position/Pedal Sensor Failure
Faulty pedal position sensor or throttle control causing limp mode and loss of acceleration, creating dangerous highway situations.
When: Approximately 70 mph highway driving
Symptoms owners cite: Engine light illumination; Limp mode activation; Loss of acceleration; Vehicle unable to cross busy road safely
Codes mentioned: P2138
Fuel System Failure
Faulty fuel pump and/or fuel tank causing repeated stalling and inability to accelerate, bringing vehicle to a halt in heavy traffic.
When: After 3-4 years of ownership
Symptoms owners cite: Failure to accelerate; Vehicle stalling multiple times in traffic; Complete power loss
Codes mentioned: None reported
Repairs/costs cited: Vehicle towed to dealership; repair status unknown at time of complaint
Synthesized from 18 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 5 most recent
I have engine light on and when I scanned it, I got a error code P052E For crankcase vent valve issues. It is most common problem with Mercedes-Benz Glc .
The contact owns a 2018 Mercedes-Benz GLC300. The contact stated that while driving 65 MPH, the vehicle started to hesitate while depressing the accelerator pedal. The contact stated that the vehicle also started shaking and vibrating with the check engine warning light illuminated. The contact managed to pull the vehicle off the highway and had the vehicle towed to a dealer. The vehicle remained…
Complete engine failure after 55,000 miles determined that there was a broken piston #1 in the car. This required a complete engine replacement. This is a known problem by Mercedes with the engine model M274 there are numerous reports of the same problem in this engine over several models and years. The engine was 5000 miles out of warranty however this problem seems to occur in alot of…
Code P052E PCV crankcase valve ventilation
Had engine trouble with your 2018 Mercedes-Benz GLC-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 GLC-Class?
It's a meaningful issue. 18 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $3,100.
At what mileage does the engine typically fail?
Based on the 18 complaints filed, engine issues most often appear around 10,600 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/GLC-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.