Mercedes M274 petrol engines with a capacity of 1.6 and 2.0 liters have been produced by the company since 2011 and are installed in vehicles with longitudinally mounted engines, such as the C-Class and E-Class. Similar engines for models with a transverse powertrain layout have the M270 index. The R4 series includes: M102, M111, M166, M260, M264, M266, M271, and M282.
| Typ | row |
| Number of cylinders | 4 |
| number of valves | 16 |
| Exact capacity | 1595 cm³ |
| Cylinder diameter | 83 mm |
| Piston stroke. | 73.7 mm |
| Power system | direct injection |
| Power | 129 - 156 HP |
| Torque | 210 - 250 nm |
| Compression ratio | 10.3 |
| Fuel type | 95 |
| Environmental class | EURO 5/6 |
| Typ | row |
| Number of cylinders | 4 |
| number of valves | 16 |
| Exact capacity | 1991 cm³ |
| Cylinder diameter | 83 mm |
| Piston stroke. | 92 mm |
| Power system | direct injection |
| Power | 156 - 245 HP |
| Torque | 270 - 370 nm |
| Compression ratio | 9.8 |
| Fuel type | 95 |
| Environmental class | EURO 5/6 |
| Typ | row |
| Number of cylinders | 4 |
| number of valves | 16 |
| Exact capacity | 1991 cm³ |
| Cylinder diameter | 83 mm |
| Piston stroke. | 92 mm |
| Power system | direct injection |
| Power | 279 - 333 HP * |
| Torque | 600 - 700 nm * |
| Compression ratio | 9.8 |
| Fuel type | 95 |
| Environmental class | EURO 5/6 |
| City | 7.9 litry |
| Route | 5.2 litry |
| Mixed | 6.2 litry |
The weight of the M274 engine according to the catalog is 137 kg. The M274 engine number is located at the junction of the block and the gearbox. Cracking of the phase regulators in engines produced before 2014 starts quite quickly, then the manufacturer improved the design and the service life increased to 150-200 thousand km. Around the same mileage, the timing chain stretches and many people change them at the same time. Displacement of the impulse disk. Many owners of cars with engines from this family complain about starting problems, and the main reason for this is the displacement of the impulse disk relative to the camshaft axis. Usually, this is indicated by an error with the camshaft position sensor. Piston destruction. In 2015, engines of this series were modernized and became slightly more fuel-efficient, but this led to more frequent detonation and piston destruction. Poor quality fuel also greatly affects the piezo direct injection injectors. Engine overheating. It is necessary to carefully monitor the condition of the power unit cooling system, as even a not very prolonged overheating can cause cylinder head failure. The problem is exacerbated by the rather low reliability of the thermostat and water pump. Other breakdowns. Leaks from under the valve cover due to a stuck PCV valve, as well as from the front crankshaft seal or heat exchanger gasket, are regularly occurring issues. Due to wiring breaks, the variable capacity oil pump valve gets stuck, the adsorber quickly becomes clogged, fuel hoses often leak, and the turbine actuator gets stuck.
| C-Class W204 | 2012 - 2015 |
| C-Class W205 | 2014 - 2020 |
| E-Class W212 | 2013 - 2016 |
| E-Class W213 | 2016 - CE |
| GLK-Class X204 | 2013 - 2015 |
| GLC-Class X253 | 2015 - CE |
| GLE-Class W167 | 2019 - CE |
| SLC-Class R172 | 2015 - 2020 |
| V-Class W447 | 2015 - 2019 |
| Q50 1 (V37) | 2014 - 2020 |
| Q60 2 (CV37) | 2016 - 2022 |
| Q70 1 (Y51) | 2018 - 2022 |
4-cylinder engines of the Mercedes M102 with a capacity ranging from 1.8 to 2.3 liters were produced from 1980 to 1993 and installed in the most popular models of the German company, such as W201, W123, and W124. Cosworth offered 16-valve versions with a capacity of 2.3-2.5 liters for sports cars. R4 series: M111, M166, M260, M264, M266, M270, M271, M274, and M282.
4-cylinder Mercedes M266 engines with a displacement ranging from 1.5 to 2.0 liters were produced from 2004 to 2012 and were exclusively installed in the compact A-Class model and its compact van counterpart, the B-Class. These power units were essentially just updated versions of the popular M166 engines. R4 Series: M111, M260, M264, M270, M271, M274, and M282.
The 1.4-liter turbocharged petrol engine Mercedes M282 has been produced by the company since 2018 and is practically installed in all front-wheel drive models: A-Class, B-Class, CLA, GLA, and GLB. This engine was developed in collaboration with the Renault group and is also known under the index H5Ht. R4 series: M102, M111, M166, M260, M264, M266, M270, M271, and M274.
The family of inline six-cylinder engines, Mercedes M103, was produced from 1985 to 1993 and was installed in many models of the company, such as W201, W124, and luxury roadsters R107. There were two different versions of the engine: E26 with a capacity of 2.6 liters and E30 with a capacity of 3.0 liters. The inline six-cylinder engine lineup also includes units: M104 and M256.
The 2.4-liter turbocharged Chrysler EDT engine was manufactured by the company from 2002 to 2009 and was only installed in turbocharged versions of the PT Cruiser model equipped with a manual or automatic transmission. This powertrain is essentially a degraded version of the well-known turbocharged EDV engine. The Neon series also includes the following engines: EBD, ECB, ECC, ECH, EDZ, and EDV.
The 2.5-liter Mazda WL-T turbodiesel engine was produced in Japan from 1995 to 2006 and used in rear-wheel drive as well as fully driven models such as MPV, Bongo Friendee, and Proceed Marvie. The modified version of this engine with electronically controlled unit injectors is often referred to as WL-TE. The same line also includes the naturally aspirated WL diesel engine.