Characteristics of the N42B18 engine
Manufacture and History
The N42B18 engine from BMW, produced at the Hams Hall plant from 2001 to 2004, is an important element of BMW’s powertrain lineup of the early 2000s. This engine was fitted to the BMW 316i E46, and is recognized for its performance and reliability.
Design and Materials
The main material of the cylinder block of the N42B18 engine is aluminum, which ensures lightness and good cooling. It utilizes an injected power system for efficient fuel injection and improved dynamic performance. The engine has an in-line configuration and consists of four cylinders, each with four valves. The piston stroke is 81 mm and the cylinder diameter is 84 mm, giving a displacement of 1,796 cubic centimeters at a compression ratio of 10.5.
Performance and Environmental Standards
The engine output is 116 horsepower at 5,500 rpm and the torque reaches 175 Nm at 3,750 rpm. This allows the car to exhibit good acceleration and traction. The engine meets Euro 3 environmental standards, making it quite eco-friendly for its time.
Weight and Economy
The weight of the engine is 120 kg, which contributes to the overall balance of the car. Fuel consumption is an important parameter: for the BMW 316i E46 it is 9.9 liters per 100 km in the city cycle, 5.5 liters on the highway and 7.1 liters in mixed mode. Oil consumption is also controlled and is up to 700 grams per 1000 km.
Service and Life
For the engine it is recommended to use oils with viscosity 5W-30 or 5W-40. The total volume of oil in the system is 4.25 liters, and 4 liters are filled when changing the oil. The recommended oil change interval is every 10,000 km to keep the engine in good condition and extend its life.
Reliability and Durability
Although there is no accurate data on the engine operating temperature, the practical life of the engine is more than 250,000 kilometers, which indicates its durability and reliability.
Reliability, problems and repairs of the BMW N42B18 engine
The new 1.8-liter four-cylinder engine BMW N42B18 was released in 2001 to replace the M43B16 and M43B18. The new engine was developed on the basis of the older N42B20, in which the long-stroke crankshaft was replaced by another one with a stroke of 81 mm (it was 90 mm). Comparing the N42B18 with the M43 generation, we can notice a new aluminum cylinder block, new connecting rods and pistons for compression ratio of 10.5. Completely new cylinder head, already 16-valve with two camshafts, with hydrocompensators, with a system of variable valve timing on the intake and exhaust shafts (Double Vanos), as well as with a system of controlling the height of the intake valves Valvetronic. Valve diameter is similar to the 2-liter counterpart: inlet 32 mm, outlet 29 mm. Characteristics of standard BMW N42B18 camshafts: phase 250/258, lift to 9.7/9.7.
The engine management system is new, now it is Bosch ME 9.2.
This motor was used on BMW cars with the index 16i.
Like the older version, N42B18 received three successors at once, in 2004 came out N45B16 and N46B18, and in 2007 the last representative appeared – N43B16.
Problems and shortcomings of BMW N42B18 engines
This BMW motor has become a real storehouse of factory defects. As is known, owners had to face interruptions in the work of the Valvetronic and increased oil consumption. The problem was caused by valve seals, which used up their resource. Also the quality of the oil poured in played an important role. After 30 thousand mileage, even with proper maintenance, the owner expected noise in the power unit and vibration in the process of its operation. In this case, the problem was in the tensioner of the timing drive (in 50% of cases the problem was the chain). Already at 50 thousand kilometers of mileage the cylinder-head gasket together with the vacuum pump had to be replaced. Owners of N46 in two-liter version had similar problems.
Tuning of BMW N42B18 engine
Chip tuning
Refining the N42 engine is a difficult and thankless business, there is nothing on the market to significantly increase the output of the motor. The only way to increase power is a trip to the tuning office for firmware and air filter replacement. These modifications will increase the power by ~10 hp, which will be very difficult to feel. If for some reason it seems not enough, then it is worth thinking about buying a powerful six-cylinder M54B25.
ENGINE RATING: 4