The BMW M43 is a single overhead camshaft eight valve four-cylinder petrol engine which was produced from 1991 to 2002. The M43 was used in lower powered models, while higher power models had the BMW M42 and later BMW M44 both sixteen valve 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 and the lower powered N40 engine in 2001, the M43 began to be phased out.
Design Compared with the BMW M40 predecessor, the M43 features camshaft position sensor and knock sensor as well as roller rockers and a timing chain (instead of the M40's finger rockers and timing belt). It also introduced a dual length intake manifold ("DISA"), to provide torque across a wider rev range.
The 1.9 litre version - the M43TU - was introduced in Autumn 1998 for use in the BMW E46 316i and 318i as well as the E36 316i Compact and BMW Z3. Basically similar to the outgoing 1.8 unit, the M43TU used the short block from the M44 twin cam engine with the rear mounted crank sensor and a new crankshaft pulley without a TDC reference cut out. The cylinder head is similar to the previous engine but the intake manifold was revised. The engine management system is Bosch Motronic, DME 1.7.3.
Versions
Version DisplacementPowerTorqueYearNoteM43B16 at 5500 rpm at 3900 rpm1991-1999 at 5500 rpm at 3900 rpm1995-2000CNGM43B18 at 5500 rpm at 3900 rpm1993 at 5500 rpm at 3900 rpm1995-1996CNGM43B19 at 5500 rpm at 3900 rpm1998 at 5300 rpm at 2500 rpm1999
M43B16 The M43B16 produces and 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 displacement. It produces and 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 . It produces up to and , and uses BMW's BMS 46 engine management system. The 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— and : 1999-2001 E36 316i Compact 1999-2002 E46 316i
Applications— and : 1998-2001 E46 318i/318Ci 1999 -2002 Z3 1.9
References
See also List of BMW engines