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.
Compared with its BMW M40 predecessor, the M43 features a knock sensor and a timing chain instead of the M40s 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 1.895 cc 115.6 cu in, increasing torque to 180 N⋅m 133 lb⋅ft at 3900 rpm.
2.1. Versions M43B16
The 1.596 cc 97.4 cu in M43B16 produces 75 kW 102 PS and 150 N⋅m 111 lb⋅ft of torque. It uses the Bosch Motronic 1.7.1 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.
- 1993-1999 E36 316i
- 1995-2000 E36/5 316g Compact
2.2. Versions M43B18
The M43B18 has a 1.796 cc 109.6 cu in displacement. It produces 85 kW 115 PS and 124 lb⋅ft 168 N⋅m 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.
- 1994-1996 E34 518i
- 1995-2001 Z3 1.8
- 1995-1996 E34 518g Touring
- 1992-1998 E36 318i
2.3. Versions M43B19
The M43B19 also known as the "M43TU" is the largest M43 engine, with a displacement of 1.895 cc 115.6 cu in. It produces up to 87 kW 118 PS and 180 N⋅m 133 lb⋅ft, and uses BMWs BMS 46 engine management system. The 77 kW 105 PS versions do not have the DISA intake manifold.
Applications - 77 kW 105 PS and 165 N⋅m 122 lb⋅ft:
- 1999-2001 E36 316i
- 1999-2001 E46 316i
Applications - 87 kW 118 PS and 180 N⋅m 133 lb⋅ft:
- 2001-2003 Z3 1.9
- 1998-2001 E46 318i/318Ci