M270/M274 engine: faults and reliability

• M270 1.6 turbo 102-156 hp

  2011–2020 · 102–156 hp · M270 DE16

  With caution

  It shares the weak points documented for the M270 in general —possible camshaft breakage on 2015 units because of a defective weld—, with the sources not identifying a pattern specific to this displacement compared with the 2.0-litre.^[3]

• M270 2.0 turbo 156-218 hp

  2012–2020 · 156–218 hp · M270 DE20

  With caution

  It shares the weak points documented for the M270 in general —possible camshaft breakage on 2015 units because of a defective weld—, with the sources not identifying a pattern specific to this displacement compared with the 1.6-litre.^[3]

• M274 2.0 turbo 156-245 hp

  2013–2023 · 156–245 hp · M274 DE20

  With caution

  It is the variant with the two most specific problems documented for this engine family: possible camshaft breakage on 2015 units and oil leaking from the camshaft adjuster into the electrical connector over the years. These are known faults but they need not stop you buying if you check for them first.^[2][3]

Buy: No known serious faults, or they have already been corrected, in this version. With caution: Worth buying if something specific is verified: history, a replaced part or a completed campaign. Avoid: High risk of a serious fault that is hard to check for or prevent.

1. 1Critical severityFrequency: OccasionalTimingCamshaft breakage due to a defective weld (2015 units)Yes: some M270 and M274 engines built in 2015 can suffer a camshaft breaking because of a poorly executed factory weld, with a risk of engine damage. It affects specific units from that year across several models, not the whole production run.
2. 2Medium severityFrequency: CommonTimingOil leaking from the camshaft adjuster into the electrical connector (M274)Yes: on the M274, the camshaft adjuster solenoids can lose their seal over the years and let oil wick up to the connector and the wiring harness, potentially reaching the ECU. It is fixed relatively cheaply with a specific repair cable.
3. 3Medium severityFrequency: OccasionalCoolingCoolant leaks: thermostat and expansion tankYes: the M270/M274 thermostat can fail and trigger code P0128, and on the M270 the expansion tank can lose its seal over the years. Both are described as occasional faults of moderate cost, not as a serious systematic fault.
4. 4Low severityFrequency: CommonEmissions controlNOx sensor failure (code P2200) on the M274Yes: the M274 can throw fault code P2200 because of a NOx sensor failure, a component of the emissions control system. A German specialist workshop describes it as a frequent fault, with a repair cost of between €100 and €500.Repair (garage): €100–€500
5. 5Medium severityFrequency: RareTimingTiming chain and tensioner: a strong point compared with earlier enginesGenerally no: unlike earlier Mercedes engines, the M270/M274 timing chain is not a common source of faults. The specialist workshops consulted agree that it hardly gives any trouble now, with only isolated cases cited online.

Severity colours: low, medium, high, critical. How we rate them

Manufacturer

Mercedes-Benz (Daimler)

Family

M270/M274

Fuel

Petrol

Displacement

1,991 cm³

Cylinders

4

Fuel system

Turbo

Injection

Direct injection

Timing

Chain

Power

102–245 hp

Peak torque

370 Nm

Production

since 2011

Makes

Mercedes-Benz

Technical data^[1][4]

1. 2011–2020

   M270 1.6 turbo 102-156 hp

   1.6-litre block (1,595 cc) for the entry-level and mid-range versions —180 and 200— of the A-Class, B-Class, CLA and GLA, with transverse mounting and BlueDIRECT direct injection; the lower-output versions also have the CAMTRONIC variable valve lift system.^[1][4]

2. 2012–2020

   M270 2.0 turbo 156-218 hp

   2.0-litre block (1,991 cc) for the most powerful versions —250— of the A-Class, B-Class, CLA and GLA, with transverse mounting and BlueDIRECT direct injection.^[1][4]

3. 2013–2023

   M274 2.0 turbo 156-245 hp

   2.0-litre block (1,991 cc) with longitudinal mounting for the C-Class, the E-Class (since the 2013 facelift), the GLC and the SLC, in the 200, 250 and 300 designations depending on the model.^{[1][5][6][7][8]}

• Timing chain kit

  • Buy part at Autodoc (affiliate link, opens in a new tab)

• Oil filter

  • Buy part at Autodoc (affiliate link, opens in a new tab)

• Air filter

  • Buy part at Autodoc (affiliate link, opens in a new tab)

• Spark plugs

  • Buy part at Autodoc (affiliate link, opens in a new tab)