From 2007 to 2011, BMW manufactured the 4-cylinder inline gasoline engine known as the N43B20. The N43 engine comes in three different versions, all of which have become well-known and popular among drivers worldwide.
The software-strangled N43B20K0 has 122 horsepower at 6000 rpm and 185 Nm of torque at 3000 rpm. The BMW model with the index 16i had the motor installed.
For BMW models with the index 18i, the N43B20U0 version has 143 horsepower at 6000 rpm and 190 Nm of torque at 4250 rpm.
The most potent version for BMW models with the 20i index is N43B20O0. 210 Nm of torque at 4250 rpm and 170 horsepower at 6700 rpm.
The new BMW N43 engine has Valvetronic valve lift systems and direct fuel injection, in contrast to the N42 engine. The engine was manufactured alongside units like the N45 and N46, but during this time, its demand outpaced that of its competitors.
This engine’s design aims to combine economy, environmental friendliness, and an optimally high torque level—a combination that is not always simple to attain.
Specifications
| Production years | 2007-2011 |
| Displacement, cc | 1995 |
| Fuel system | direct injection |
| Power output, hp | 122 /6000 rpm 143 /6000 rpm 170 /6700 rpm |
| Torque output, Nm | 185 /3000 rpm 190 /4250 rpm 210 /4250 rpm |
| Cylinder block | aluminum R4 |
| Block head | aluminum 16v |
| Cylinder bore, mm | 84 |
| Piston stroke, mm | 90 |
| Compression ratio | 12.0 |
| Features | no |
| Hydraulic lifters | yes |
| Timing drive | chain |
| Phase regulator | double VANOS |
| Turbocharging | no |
| Recommended engine oil | 5W-30 |
| Engine oil capacity, liter | 4.25 |
| Fuel type | petrol |
| Euro standards | EURO 4/5 |
| Fuel consumption, L/100 km (for 320i E90) — city — highway — combined |
8.3 5.3 6.4 |
| Engine lifespan, km | ~250 000 |
Disadvantages of the N43B20 engine
Motor housing vibrations. The N43 frequently experiences this breakdown as a result of injector failure. As a result, the latter will need to be completely replaced.
Engine speed variations and trocking. The ignition coils that failed are the reason for the breakdown. Replacement is necessary.
Vacuum pump leak. This kind of drawback frequently occurs every 70,000 kilometers. Replacing the device is the only way to resolve the issue.
In order to prevent overheating, the cooling system must always be inspected. Furthermore, this series’ power unit uses a lot of fuel and oil. Quality control is especially important for oil. The engine’s high temperature operation will cause the uncertified oil to deteriorate right away, which will cause major issues later on. As a result, it is advised to use only the oil that the manufacturer recommends for N43B20. The engine will run longer than its intended resource if it is properly maintained and cared for.