Mercedes-Benz B 160
Modular four-cylinder turbo of the first compact platform generation. Known for timing chain stretch and thermostat issues. Adequate power up to 156 hp.
Base Is Enough
75 kW in the van body of the B-Class: enough for town, but the engine is too weak to move the weight with ease.
Engine Weaknesses 7
The sealing ring on the camshaft adjuster solenoid fails. Oil creeps by capillary action through the wiring harness and destroys lambda sensors and the ECU. Repair €1,700–€4,000.
Symptoms: Lambda sensor fault codes, engine stumbling, CEL. In later stages multiple electrical faults simultaneously, ECU coated with oil
M270 engines with manufacturing date July–September 2015 have a defective weld seam on the camshaft lobe. Camshaft can break → engine damage. Recall with free replacement.
Symptoms: Sudden engine noise, power loss up to engine stall. Only vehicles with production date July–September 2015 affected
The electrically-controlled thermostat on the M270 fails frequently and is difficult to access at the rear of the engine. Replacement costs 800–1,300 EUR at Mercedes workshops.
Symptoms: Engine does not reach operating temperature of 80°C, coolant temperature fluctuates, fault code P0128
M270 camshaft adjusters wear from 100,000–130,000 km and generate rattling noises on cold start. Revised adjusters fitted from 2014 onward.
Symptoms: Brief rattling or clattering after cold start from engine bay, disappears after warm-up
The electronically controlled thermostat on the M270DE16 fails frequently and throws fault code P0128. Engine fails to reach operating temperature or overheats sporadically. Repair at Mercedes €800–€1,000.
Symptoms: Temperature gauge stays low or fluctuates, CEL, increased fuel consumption, fault code P0128
Direct injection without port injection causes carbon deposits on the M270 intake valves. Cleaning by walnut shell blasting required.
Symptoms: Hesitation at part throttle, rough idle, slight power loss, elevated fuel consumption
Ignition coils on the M270DE16 fail sporadically and cause misfires in individual cylinders. Engine runs roughly, CEL illuminates.
Symptoms: Stumbling and rough engine at low revs, CEL flashing or permanently lit, cylinder-specific misfire fault codes
Vehicle Weaknesses 5
Collision warning system incorrectly detects obstacles in urban traffic and initiates autonomous emergency braking. Software update resolves the problem. Rear light failures also known.
Corroded connectors on the ECU cause failure of ESP, ABS and PRE-Safe. Safety systems are deactivated, vehicle goes into limp mode.
Door lower edges of the W246 rust, though less severely than the predecessor. Axle springs and components corrode and can break through oxidation. Rust susceptibility inappropriate for the price level.
A/C condensers can develop leaks and lose refrigerant. A/C cooling diminishes after several years. Problem less frequent than on the predecessor W245 but still present.
Brake discs and brake hoses wear above average on the W246. MOT reports flag this regularly. Brake lines on older examples are prone to corrosion.