BMW M43B19TU engine

Today we are going to talk about BMW M43 B19TU engine.  BMW M43 was produced from 1991 to 2002. The engine capacity is from 1.6 to 2.0 liters. It is a four-cylinder piston engine with SOHC system.

Engine specifications M43B19TU

Advantages

The power unit was equipped with an engine block with balancer housing mounting points, which reduced vibration from the power unit operation and allowed to place it closer to the passenger compartment.  Cylinder block with engine speed sensor assembly and reference signal sensor allowed more accurate monitoring of engine condition and made maintenance much easier. The crankshaft with drive gear strengthened the overall structural integrity.

The new balancer shaft assembly has increased the performance and drivability of the powertrain by 17%. A modified camshaft eliminates low-speed power dip. Specially designed pistons and connecting rods with longer stroke also added to the performance of the powerplant.

The M43 has a two-pass intake manifold unlike its predecessor, the M40. A system called “E36 Individual Intake Manifold” from BMW is used to provide torque over a wider rev range.

The SOHC system, which is the basis of the M43, has a single camshaft with two valves per cylinder. A chain drive drives the camshaft, unlike the previous M40 series engine which used a belt.

The timing mechanism consists of drive and driven sprockets, tensioner and damper. Lubrication of the system elements consists of pulling the timing chain through the crankcase with oil to the lower edge of the drive sprocket. Oil gets on the other parts of the chain links. Tension control is carried out during service maintenance.

For the first time, the concept of variable geometry is introduced, which ensures torque stability under different engine operating conditions. At low crankshaft speeds, the air supply is reduced, if you increase the rpm, the system switches the air supply to full. The system, developed by the company’s engineers, got its own name as an abbreviation for DIVA. From the very beginning, this engine was equipped with a fuel injection system from German corporations such as Bosch. The Motronic 1.7.1 injector has proven to be reliable and a system that provides optimal parameters for its operation. The digital unit combined the functions of performance monitoring and direct control of fuel supply and ignition of the mixture in the cylinders.

Disadvantages

As for problems, this engine is characterized by oil leaks. It appears on the order of 70 thousand mileage, and is corrected by replacing the gasket with sealant. This is a common thing for engines of this series. Often the flap of the engine power system fails. It emits extraneous noises, knocking crackle. It is necessary to check the DISA damper, look at the cause of the malfunction and the entire intake system. But the problem may also lie in the knocking of hydrocompensators.

In addition, this powertrain has problems that are common to the M40 series engines. Among them are power dips that occur during acceleration, extraneous noises and floating rpm of the power unit, especially at idle speed. And the propensity of the engine to overheat. But the most important disadvantage is the performance laid down by the factory.

The engine absolutely does not correspond to the BMW brand as a manufacturer of sports cars. To summarize, despite the shortcomings, our engine is quite comfortable and reliable. It has a good resource, especially with proper care and maintenance. Without problems, the engine can go more than 250-300 thousand kilometers. However, when buying a car with this engine, do not count on the ideal condition of motors. Today, the engine has driven off its resource. Therefore, carefully check the powertrain for the problems that we have indicated above.

Modifications

The M43TU was first introduced in 1998. It turned out to be a modified version of the M43B18. The new engine has an improved cylinder block for shaft balancing. The cylinder dimensions were increased to 85 mm. A new crankshaft was installed with a stroke of 83.5 mm. The pistons and connecting rods have also been modified.

No changes were made to the cylinder head except for lower power and a new camshaft. The DISA intake manifold was made of plastic.

The engine was equipped with a Bosch BMS 46 control system. This engine was mainly used in the BMW 16i and 18i models. Along with this, production of the 16V M44B19 engine was launched In 2001, the M43TU engine was replaced by the new 2-liter N42B20 engine

1. M43TU B19 OL (1998 2002) base version with 118 hp at 5500 rpm, 180 Nm of torque at 3900 rpm.
2. M43TU B19 UL (1998 2001) is a new version with less power, another camshaft. It produces 105 hp at 5300 rpm, 165 Nm of torque at 2500 rpm.

BMW M43 B19TU is a more refined version of the M43B18/M43B16 modification. The main changes are the modification of the main cylinder block, which was specially designed for the new balancer shafts. Another major modification, which was made by Bavaria Motors, is the mounting points for the new pistons, which are 85 mm. The crankshaft has an increased stroke, and the pistons and connecting rods have undergone serious changes. The cylinder head has not undergone major changes. On the weaker version of the power unit, only the camshaft has been changed.

Changes were made to the exhaust manifold, which became plastic. A new engine management system was added. Now it is Bosch BMS 46.As for cars with this engine, it was installed on all German cars with the index16i and 18i. The power unit has a related model that has a cylinder head with 16 valves – the V-shaped M44B19.

But in 2001, a new engine N42B20 was released, which replaced our protagonist. More about the modifications.

There is a version of the engine with the index M43B19 OL that was produced from 1998 to 2002, this is the base variation of the powertrain that has a power output of 118 horsepower and it is achieved at 2500 rpm. These powertrain models have a torque of 180 Newtons per meter, which are achieved at 3900 rpm. And the second modification is the M43B19 UL. It was released for the years 1998 through 2001. It is a weaker version that had a modified camshaft. Power was around 105 horsepower and was achieved at 5,300 rpm. Torque was around 165 Newtons per meter and was produced at 2500 rpm.

Characteristics

The power units were produced at Steyr Plant under the brand name M43. It was produced from 1998 to 2002. The material from which the cylinder block is made is cast iron. The fuel mixture is mixed with air in the injector. The engine type is in-line, 4-cylinder, 2 valves per cylinder. The piston stroke is 83.5 mm and the cylinder has a diameter of 85 mm. The compression ratio is 9.7 units. The exact volume of the engine is 1895 cubic centimeters. Depending on the modification, the engine output ranges from 105 horsepower at 5,300 rpm to 118 horsepower at 5,500 rpm. Torque is 165 Newtons per meter at 2,500 rpm, and 118 Newtons per meter at 5,500 rpm. The engine uses fuel with an octane number of 95 and meets the environmental standards that are present in the requirements of Euro-3. The engine weighs about 140 kg. In order to measure the average fuel consumption, we took a BMW 318i in 46 body as an example.

In the city the on-board computer showed about 11-11. 5 liters for every 100 km on the highway in 6 L. In the mixed cycle of about 8. Like the rest of the engine from BMW, the average oil consumption for each 1000 km is about 1 liter.

The oil is filled with 0W-30 0W-40 5W-30 and 5W-40 grades. There are about 4 liters of lubricant in the engine. According to the technical regulations in the documentation, replacement of fluids should be carried out every 7-10 1000 km with mandatory cleaning of the entire system with industrial alcohol. The operating temperature of the engine is about 90-95 degrees Celsius. According to the factory, the engine resource exceeds 350 000 + kilometers, in practice it comes to more than half a million. Everything depends on the correct use of power, careful attitude and timely replacement of consumables.

Chip tuning

The tuning potential is about 150 horsepower, we are talking about an upgrade, without loss of resource.As for serious intervention, it all depends on the quality of workmanship and the level of parts you install on the power units.

You can take a more painless route and limit yourself to installing a cold intake, a sport intake manifold and a new camshaft. Engine flashing will also help. All these manipulations can additionally squeeze out of this power unit about 30-40 horsepower, but taking into account the loss of power at low speeds.

This engine is installed on the following models:

BMW 3-Series (E46)