BMW N42B20 Engine Specs, Problems & Reliability

BMW N42B20 Engine – Here in this post, I have taken all the details about BMW N42B20 Engine from the (official site) including BMW N42B20 Engine specs, Weight, Price & Dimension.

We believe to provide accurate details to our readers and we prefer only official sources for information about BMW N42B20 Engine.

All the details which you want to know about BMW N42B20 Engine you can find in this article which is updated.

BMW N42B20 Engine

In 2001, the 4-cylinder N42B20 engine replaced the M43B18 and HTML43B19 obsolete engines. The new engine used a lighter aluminum cylinder block with cast iron liners instead of the heavy cast-iron one.

The N42B20 engine features a new 90 mm stroke crankshaft with long stroke and new connecting rods and pistons. The M43TU’s balance shafts are unchanged but have been adapted to the new block.

The SOHC 8V replaced a new 16-valve twin-shaft 16V cylinder head. The new cylinder head features a variable valve timing system for Double-VANOS shafts and a Valvetronic intake valve lift system.

The intake valves are 32 mm in diameter, and the exhaust is 29 mm. The standard BMW N42 camshafts have the following characteristics: Phase 250/258 rises to 9.7/9.7.

The N42B20’s intake manifold is fitted with a DISA variable length control system. This dramatically optimizes performance at low and high speeds. Bosch ME 9.2 engine management system.

This motor was used in BMW cars that had the 18i index.

BMW N42B20 Engine

BMW N42B20 Engine Specs

The inline 4-cylinder, two-liter, four-cylinder engine was launched in 2001 to replace old M43TU, M43TU, and M44B19 engines. All modern technology and systems were available to the N42B20 engine back then.

Cast-iron sleeves are used instead of a cast-iron block to make the engine. This engine is lighter than the previous inline-four BMW engines.

The cylinder block now has a new 90 mm stroke crankshaft and pistons. The N42B20 engine has the same balancing shafts as the M43TU engine. Engineers made minor changes to accommodate them in the new cylinder block.

ManufacturerBMW Plant Hams Hall
Production years2001-2004
Cylinder block materialAluminium
Cylinder head materialAluminium
Fuel typeGasoline
Fuel systemFuel injection
Number of cylinders4
Valves per cylinder4
Valvetrain layoutDOHC
Bore84.0 mm
Stroke90.0 mm
Displacement1995 cc
TypeFour-stroke, naturally aspirated
Compression Ratio10:1
Power143 hp (105 kW) at 6,000 rpm
Torque148 lb-ft (200 Nm) at 3,750 rpm
Firing order1-3-4-2
Engine oil weight5W-30, 5W-40
Engine oil capacity4.25 litres
Oil change interval6,000 miles (10,000 km) or 12 months
ApplicationsBMW E46 318i, 318Ci, 318ti

BMW N42B20 Engine Problems & Reliability

Diesel sound. Timing chain reliability could be better. It could be a stretched timing chain or its tensioner causing the noise.

The life expectancy of a timing chain is approximately 60,000 miles. Spark plugs changes can cause ignition coils BREMI to be damaged.

Make sure the radiator is in good condition. The engine will begin to use oil after a slight overheating. This is due to a weak valve stem seal.

You should also know that the N42B20 motor demands high oil quality. Follow the manufacturer’s recommendations for engine oil.

It is packed with modern technology and electronics. It is also as reliable and long-lasting as the M40 and M43 engines.

BMW N42B20 Disadvantages

Overheating. Polluted radiators are the main culprit for this problem. Regular cleaning is necessary. Broken thermostats should be replaced at 60,000 miles (100,000 km) of travel.

Motor oil consumption will increase if valve stem seals are out of alignment. Pay attention to the operation of your cooling system.

N42 noise. This problem can be solved by replacing the timing chain tensioner. It should be replaced every 60,000 miles (100,000km).

The timing chain for N42 could be more reliable. It makes a loud noise and stretches out every 60,000 miles (100,000. km).

Also, BREMI ignition coils can become out of alignment while replacing spark plugs. You should replace BREMI ignition coils if you experience this problem.

Motor oil is subject to N42. This is why it is essential only to use the recommended motor oil by your auto manufacturer. Lower quality oil can cause damage to your vehicle, such as Vanos replacement or rebuild.

N42 can be summarized as a technological and economic engine. It can also be quite demanding. It is as reliable as the M40–M43 series. This means that it requires regular inspection, control, and quality maintenance.

BMW N42B20 Engine 

BMW produced the BMW N42B20, a 2.0L four-cylinder naturally aspirated petrol engine from 2001 until 2004. The first BMW engine with Valvetronic was produced between 2001 and 2004. For a full review, please check this YouTube video Here.

BMW N42B20 Engine FAQs

What BMW has the N42 engine?

The N42 is the base for the N40 engine, which does not have Valvetronic. 2001 International Engine of the Year Awards, 1.4-1.8L category. The N42B18 was awarded this award. The N42 four-cylinder engine was replaced in 2004 by the BMW N46.

What is the difference between BMW N42 and N46?

The N46 has a modified crankshaft, intake manifold, and valvetrain compared to its N42 predecessor. The N46N was introduced in 2007. The intake manifold, exhaust camshaft, and engine control unit were all changed from Bosch Motronic version ME9. Version MV17 to 2.

Is BMW N46 engine good?

The N46 engines are reliable and robust units. As long as you follow the manufacturer’s service schedules and use good-quality oil, they will last.

What is the strongest BMW engine?

The BMW M5CS was introduced in 2021. It is the most powerful production vehicle from a German manufacturer. The 4.4-liter V-8 produces 627 horsepower and enables all M-badged Bimmers to be outgunned by the M5 CS.

Is N46 better than N42?

They are nearly identical. The only difference is that VVT is on the N42 and the N46. It is easy to see if you open up the engine bay between them.

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