In-line 4-cylinder BMW N42B18 engines have a DOHC gas distribution system. The M43 series engines served as the model’s predecessor. The two overhead camshafts and the cutting-edge VANOS system are the N42B18’s primary features. Both fuel consumption and outlet gas pollution could be decreased thanks to this technology. Additionally, by optimizing the cylinder filling with the mixture, valvetronic technology helps to increase power.
Specifications
| Production years | 2001-2004 |
| Displacement, cc | 1796 |
| Fuel system | injector |
| Power output, hp | 116 /5500 rpm |
| Torque output, Nm | 175 /3750 rpm |
| Cylinder block | aluminum R4 |
| Block head | aluminum 16v |
| Cylinder bore, mm | 84 |
| Piston stroke, mm | 81 |
| Compression ratio | 10.5 |
| Features | Valvetronic |
| 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 3 |
| Fuel consumption, L/100 km (for 316i E46) — city — highway — combined |
9.9 5.5 7.1 |
| Engine lifespan, km | ~250 000 |
| Weight, kg | 120 |
Disadvantages of the N42B18 engine
Temperature increase. The primary causes are inadequate radiator cleaning and a broken thermostat that only needs to be replaced every 100,000 kilometers. The valve stem seals failing is the result of this. The unit uses too much oil as a result. As a result, you should constantly check the cooling system.
Noise. The chain tensioner needs to be replaced entirely in order to fix the breakage. It is defined as plus or minus 100,000 kilometers. Additionally, you must inspect the timing chain, which may stretch concurrently and increase noise.
Additionally, you should consider that the BREMI ignition system’s coils frequently deteriorate when spark plugs are changed. The latter should be changed to EPA. The powertrain of the N42 adores high-quality oils. Pouring only the one that the manufacturer recommends is preferable. Because of the engine’s high heating temperature and oil conservation, overhauls are typically required. The vanos will frequently need to be replaced as well.
The motor is very functional and economical, but it is also not as dependable as its predecessors, the M40-M43, and is highly erratic, requiring constant monitoring.