BMW M43

The BMW M43 is an SOHC four-cylinder petrol engine which was produced from 1991-2002. The M43 powered base-model cars, while higher performance models at the time were powered by the BMW M42 and BMW M44 DOHC engines. The M43 was produced at the Steyr engine plant.

A version using natural-gas was produced for the E36 318i and the E34 518i.

Following the introduction of the BMW N42 engine in 2001, the M43 began to be phased out.

Design
Compared with its BMW M40 predecessor, the M43 features both a camshaft position sensor and a knock sensor as well as roller rockers and a timing chain (instead of the M40's finger rockers and timing belt). It also features a dual length intake manifold ("DISA"), to provide torque across a wider rev range.

In 1998 the displacement was increased to 1895 cc, increasing torque to 180 Nm at 3900 rpm.

M43B16
The 1596 cc M43B16 produces 75 kW and 150 Nm of torque. It uses the Bosch Motronic 1.7.x and Bosch BMS43 engine management system. There was also a natural gas-powered version of this car (also able to run on petrol) for the 1995 BMW 316g Compact.

Applications:
 * 1994-1998 E36 316i
 * 1995-2000 E36/5 316g Compact
 * 1998-1999 E46 316i

Engine Management Systems:
 * 1993-09/1995 Bosch Motronic 1.7.2
 * 1995-09/1997 Bosch Motronic 1.7.3
 * 1997-2000 BMS43

M43B18
The M43B18 has a 1796 cc displacement. It produces 85 kW and 168 Nm and uses the Bosch Motronic 1.7.1 fuel injection system. There was also a less powerful natural gas-powered version of this car (also able to run on petrol) for the BMW 518g Touring (E34). This model was only available for two years.

Applications:
 * 1992-1998 E36 318i
 * 1994-1996 E34 518i
 * 1995-1996 E34 518g Touring
 * 1995-2001 Z3 1.8

M43B19
The M43B19 (also known as the "M43TÜ") is the largest M43 engine, with a displacement of 1895 cc. It produces up to 87 kW and 180 Nm, and uses BMW's BMS 46 engine management system. The 105 PS versions do not have the DISA intake manifold and also have a smaller camshaft compared to the 118 PS versions. Note the M43B16, M43B18 and the M43B19 (118 PS version) all have the same camshaft.

Applications— 77 kW and 165 Nm:
 * 1999-2001 E36 316i Compact
 * 1999-2002 E46 316i

Applications— 87 kW and 180 Nm:
 * 1998-2001 E46 318i/318Ci
 * 1999 -2002 Z3 1.9