Mercedes-Benz CLA 250
More powerful 2.0L variant of the M270. Solid turbocharged four-cylinder with adequate performance. Oil consumption possible at high mileage.
Stylish Sports Estate
160 kW and Shooting Brake body — practical, stylish and genuinely quick. An underrated package.
Engine Weaknesses 7
A leaking camshaft adjuster solenoid allows oil to migrate into the wiring harness. Lambda sensors die first, then the engine ECU. Well-known failure pattern on all M270 variants.
Symptoms: Lambda fault codes, rough running, CEL. Oil smell in engine bay. In later stages multiple electrical faults
M270DE20 engines with manufacturing date July–September 2015: defective weld seam on the camshaft lobe leads to fracture and engine damage. Recall with free replacement.
Symptoms: Metallic noises from engine bay, power loss, in worst case engine stall
Identical issue to the M270DE16: electrically-controlled thermostat at the rear of the engine fails prematurely. Difficult removal drives workshop costs to 700–1,300 EUR.
Symptoms: Engine runs permanently below operating temperature, coolant temperature fluctuations, fault code P0128
M270 2.0 camshaft adjusters tend to wear from approx. 100,000 km with rattling noises on cold start. Revised adjusters from model year 2014.
Symptoms: Metallic clattering or rattling directly after cold start, idle hesitation, disappears after warm-up
Just like the M270DE16, the electronically controlled thermostat on the M270DE20 also fails early. Fault code P0128, irregular coolant temperature.
Symptoms: Temperature needle stays in the lower range or fluctuates, CEL, increased fuel consumption, code P0128
The variable oil pump control valve on the M270 can fail and trigger fault code P06DA. Wiring harness to the control valve frequently breaks.
Symptoms: Fault code P06DA00, check engine light, possibly reduced engine power
On direct injection engines, oil carbon from the crankcase ventilation builds up on the intake valves. Noticeable power loss from approximately 80,000–120,000 km.
Symptoms: Stumbling at low revs, power loss, increased consumption, cold-start problems, engine roughness at partial load
Vehicle Weaknesses 7
Multiple recall actions on the CLA C117 concerned cracked fuel lines in the engine bay as well as brake booster deficiencies and faulty airbag cable routing. Affected vehicles should be checked for open recalls at the KBA.
The 7-speed dual clutch gearbox in the CLA C117 tends toward juddering gear changes, especially when pulling away and in traffic. Clutch packs wear prematurely with intensive urban use. Software updates help temporarily; at high mileages a gearbox oil change is needed.
Defective cable guides on door locks cause central locking to fail. Moisture ingress into the footwell trim puts additional strain on the electrics.
Water enters the footwells through sealing defects, which can lead to electrical damage and corrosion. Vehicles with panoramic roof are particularly affected.
According to ADAC breakdown statistics, the starter battery is the most common breakdown cause on the CLA C117. The high quiescent current draw from numerous control units drains the battery quickly during short-distance use or extended standing.
Despite its premium positioning, the CLA C117 showed sub-optimal panel gaps at door trim panels and self-releasing trim strips. Owners report squeaking and rattling noises from the interior that worsen with vehicle age.
CLA C117 owners report comparatively early brake disc wear on the front axle. Brake pads and discs often due from 40,000–50,000 km. Sporty driving style and AMG Line models more severely affected.
Reports & Tests
530 owner complaints filed with NHTSA (2013–2019). Most reported: Engine (145), Electrical (95), Other (93).