The M102 engine family is a inline-four gasoline automobile engine family built by Mercedes-Benz in the 1980s and early 1990s. It is a relatively oversquare engine with a large bore and short stroke compared to the M115 engine which was used during the same timeframe.

M102.910

Used in the W201 190E 1.8 from 1990 onwards (badged as 180E in Australia from 1991 to 1993). Cubic capacity: 1797 cc. Power output: 80 kW. Torque: 154 Nm Applications:

M102.920

The M102.920 was a 2.0 L engine with an bore and stroke 89x80.25 mm. Equipped with carburetor 175 CDT. Cubic capacity: 1997 cc. Power output: 80 kW. Swedish and Swiss market models developed 98 PS at 5000 rpm thanks to their stricter emissions regulations. Applications:

M102.921

Similar to M102.920, but less power due to a different camshaft and different carburetor. Power Output: 66 kW Applications:

M102.922

An update of the M102.920 engine for use in the W124 chassis, Cubic capacity: 1997 cc. Power output: 80 kW. During 1989 the bore was shrunk by 0.05 mm, bringing the displacement down to 1996 cc. This change was applied across the board of all 2.0 and 2.3-litre M102 engines as part of running updates carried out between 1988 and 1990. Applications:

M102.924

Similar to M102.921, different carburetor, single-belt drive for alternator, power steering pump and air-conditioning compressor (where fitted). Hydraulic aided valvetrain. Power output: 77 kW. Application

M102.938

Low compression version of M102.921. Power output: 63 kW. Application

M102.939

Low compression version of M102.920. Power output: 74 kW. Application

M102.961

A 2.0 L multi-point fuel-injected (KE-Jetronic) variation of the M102.921. An "E" was added to the model of the vehicle (standing for "einspritzung", the German word for fuel injection). This engine is identified by TSZ ignition and multiple belts for the alternator, power steering and air conditioning compressor (where fitted). Cubic capacity: 1997 cc. Power output: 90 kW Application

M102.962

An update to the M102.961 introduced in 1985. This is identified by the EZL ignition system and a single accessory drive belt. Cubic capacity: 1997 cc. Power output: 87–90 kW (118-122 PS; 117-120 bhp) Applications:

M102.963

2.0–litre version with KE-Jetronic fuel injection. Cubic capacity: 1996 cc. Power output: 90 kW Applications:

M102.964

2.0–litre version with KE-Jetronic fuel injection for the italian W460. Cubic capacity: 1997 cc. Power output: 90 kW Applications:

M102.980

The M102.980 was a 2.3 L version with a 95.5 mm bore and the same 80.25 mm stroke. Engine weight was 118 kg. Used K-Jetronic fuel injection. Cubic capacity: 2299 cc. Power output: 100 kW Applications:

M102.981

The M102.981 was a 2.3 L version with a 95.5 mm bore and the same 80.25 mm stroke. Cubic capacity: 2299 cc. Power output: 92 kW Applications:

M102.982

Similar to the M102.980 version, but with the newer KE-Jetronic system from Bosch. Cubic capacity: 2299 cc. Power output: 97 kW Applications:

M102.983

A 16-valve version of the M102.985 with cylinder head designed by Cosworth.Cubic capacity: 2299 cc. Power output: 138 kW; USA: 125 kW Applications:

M102.985

An 8-valve M102 with a displacement of 2.3 L used in the W201 chassis with KE-Jetronic fuel injection. Cubic capacity: 2299 cc. Power output: 97 kW Applications:

M102.990

An update of the 16-valve version with increased capacity (2.5 L) and stiffening ribs, still with a cylinder head designed by Cosworth. Cubic capacity: 2498 cc. Power output: 150 kW Applications:

M102.991

An update of the 2.5 16-valve version, with shorter stroke and larger bore. H beam rods and piston cooling jets. Cubic capacity: 2463 cc. Power output: 147 kW Applications:

M102.992

An update of the 102.991 version with removal of four crankshaft counterweights and even more stiffening ribs for higher RPMs. Single timing chain, oil pump with separate drive chain. Bigger intake manifold, camshaft and exhaust system. Higher compression ratio 10.5:1. Cubic capacity: 2463 cc. Power output: 173 kW Applications: