The contact owns a 2015 Mercedes-Benz GLA250. The contact stated when the vehicle was started, the check engine warning light illuminated, and there were fumes from the exhaust entering the cabin of the vehicle. Additionally, while driving at various speeds, the vehicle stalled. The contact stated that the failure persisted. The vehicle was taken to the dealer to be diagnosed; however, the…
2015 Mercedes-Benz CLA-Class engine problems
severe Owners of the 2015 Mercedes-Benz CLA-Class have filed 28 NHTSA complaints about the engine, typically surfacing around 40,000 miles 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 →
Failure mileage
Complaints
28
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2014 CLA-Class | 35 |
| 2015 CLA-Class (this page) | 28 |
| 2016 CLA-Class | 7 |
| 2017 CLA-Class | 3 |
| 2018 CLA-Class | 5 |
| 2019 CLA-Class | 5 |
1crash
1injury
When does it fail?
Of the 28 engine complaints filed for the 2015 Mercedes-Benz CLA-Class, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 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
Owners have filed 28 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.
Among the 6 model years of Mercedes-Benz CLA-Class in our records for engine problems, this one ranks #2 by owner-complaint volume.
The failure pattern owners describe
Owners report two distinct engine problems on the 2015 Mercedes-Benz CLA-Class.
The first is crankcase ventilation system failure, the dominant issue across 19 complaints. Owners describe check engine light illumination with diagnostic code P052E (or variants like P052E71, P205E) indicating positive crankcase ventilation regulator valve malfunction. Failures occur between 43,000 and 98,000 miles. Symptoms include loss of engine power while driving at various speeds—sometimes sudden and complete, forcing vehicles to stall in traffic or on highways—along with oil leaks and exhaust fumes entering the cabin. Owners report Mercedes issued an extended emissions warranty covering this defect on certain model lines (C-Class, GLC300) but excluded the CLA250 and GLA250 despite using identical engine components. Repair costs cited range from $2,000 to $4,000, with labor-intensive removal of motor mounts and engine hoisting required to access the valve assembly.
The second failure mode involves engine mechanical damage. Three complaints describe sudden loss of power and stalling at low mileage: one owner needed engine replacement at 124,000 miles, another experienced a crankshaft weld failure requiring motor replacement, and a third was diagnosed with water damage to the engine at 25,000 miles (though the vehicle had never been submerged). Two additional complaints cite water pump failures causing overheating, including a seized valve within the water pump at 37,800 miles and overheating issues shortly after warranty expiration at 10,270 miles. One owner reports oil pan vulnerability to road debris impact causing engine lockup. A separate complaint describes unexpected transmission neutral shift and stalling unrelated to the crankcase issue.
Same Mercedes-Benz CLA-Class engine reports on nearby years: 2014
Failure modes owners describe
Positive Crankcase Ventilation (PCV) Regulator Valve Malfunction
Crankcase ventilation regulator valve performance degradation leading to check engine illumination, oil system contamination, and loss of engine power. Owners report Mercedes issued an extended emissions warranty for this defect on certain model lines (C-Class, GLC300) but excluded CLA250 and GLA250 despite identical engine design and components.
When: 43,000 to 98,000 miles
Symptoms owners cite: Check engine light illumination; Sudden loss of engine power while driving; Engine stalling at various speeds; Excessive oil leakage; Oil contamination in electronic lines (owner allegation); Exhaust fumes entering cabin; Slow acceleration when stopped or at idle
Codes mentioned: P052E, P052E71, P205E
Repairs/costs cited: Repair costs $2,000 to $4,000. Regulator valve alone costs approximately $70 but sold only as part of larger assembly (approximately $700). Installation requires removing motor mounts and hoisting engine for 6–8 hours labor. Owners reference TSBs MC-10241531-0001 and LI01.20-P-076894 covering intake-line assemblies on M270 engine models.
Recalls/TSBs owners mention: Extended emissions warranty issued for certain 2015–2019 models (C-Class, GLC300) but excludes CLA250 and GLA250 despite identical components. No recall issued for excluded models.
Engine Power Loss and Stalling (Undetermined Mechanical Cause)
Sudden loss of motive power and stalling while driving at various speeds, with vehicles failing to restart. Two independent mechanics advised engine replacement in one case; another owner cited crankshaft weld failure as root cause.
When: 55,000 to 124,000 miles
Symptoms owners cite: Sudden loss of motive power; Engine stalling while driving; Vehicle fails to restart; Slow starting when turning key or pressing push-start button
Repairs/costs cited: One owner received recommendation for complete engine replacement from two independent mechanics but did not repair. Another owner reported crankshaft weld failure requiring new motor.
Water Pump Valve Seizure and Coolant Leakage
Water pump valve failure preventing coolant circulation, causing engine overheating. Owners report Mercedes replaced old-style water pump design with new version due to known defects, but customers with early serial units were not notified.
When: 10,270 miles to 37,800 miles (both cases shortly after or at warranty expiration)
Symptoms owners cite: Engine overheating warning; Seized valve in water pump; Coolant leak; Overheating during operation, stationary, or idle
Repairs/costs cited: Mercedes replaced water pump design due to known defect with old-style pump; owners report lack of notification about the issue or preemptive replacement.
Recalls/TSBs owners mention: Mercedes designed replacement water pump but did not notify owners of older-design defect or proactively replace failing units.
Oil Pan Vulnerability to Road Debris Impact
Oil pan design insufficiently protected against impact from roadway debris, leading to cracking and rapid oil loss without timely low-oil warning, resulting in engine lockup.
When: Not specified
Symptoms owners cite: Oil pan cracking from roadway debris impact; Engine lockup due to rapid oil loss; Insufficient warning time for driver to exit roadway safely
Repairs/costs cited: Owner questions strength of material and design; requests protective skid plate or guard.
Transmission Neutral Shift and Loss of Drive
Unexpected shift into neutral while driving at various speeds, accompanied by error messages, without driver input. Occurred five times across different driving conditions.
When: Not specified
Symptoms owners cite: Unexpected shift to neutral without driver command; Error message 'TRANSMISSION MALFUNCTION STOP'; Error message 'SERVICE REQUIRED DO NOT SHIFT GEARS VISIT DEALER'; Vehicle coasts and loses power; Resolved by vehicle restart
Synthesized from 28 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 3 most recent
)n 6/15/20 while driving to a doctors appointment on the highway, my engine suddenly overheated and it warned me to pull over immediately. The vehicle had 37,800 miles on it. On diagnosis, it was found that a valve in the water pump had seized from a coolant leak, preventing it from opening and circulating coolant into the engine. Unfortunately, the car was just out of warranty.,
The contact owns a 2015 Mercedes-Benz CLA250. The contact stated that the vehicle was taken to a local dealer and the vehicle starting very rather slowly. The vehicle was diagnosed however, no cause for the failure was found. The contact stated that the vehicle operated normally; however, the following day while driving approximately 50 MPH, the vehicle started to lose automotive power. The…
Had engine trouble with your 2015 Mercedes-Benz CLA-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 2015 Mercedes-Benz CLA-Class?
It's a meaningful issue. 28 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?
Across the 12 complaints that reported odometer mileage, most engine failures cluster between 25,419 and 90,000 miles, with the median around 40,000. A quarter of owners report trouble before 25,419; a quarter make it past 90,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
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/2015/Mercedes-Benz/CLA-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.