Info
BMW N46 straight-4 Engine
From 2004 to 2015

The BMW N46 is a straight-4 DOHC piston engine which replaced the N42 and was produced from 2004 to 2015.
Compared with its N42 predecessor, the N46 features a revised crankshaft, intake manifold and valvetrain. In 2007, the N46 was updated, which was known as the N46N. Changes included the intake manifold, exhaust camshaft and the engine control unit was changed from Bosch ME9.2 to Bosch MV17.4.6.
The BMW N46 is a four-cylinder gasoline engine of the car manufacturer BMW , he replaced the N42 . The N46 had its debut in 2003 in the 3 Series ( BMW E46 ) and was also offered in the same year in the E87 120i .
The development of the N46 focused on fine-tuning the engine without changing any major design features compared to the N42. The following assemblies have been changed:
- balancer shafts
- pleuel
- spark
- vacuum pump
- Roller cam
- Cylinder head cover
- Use of the DME Bosch MEV 9.2 with integrated Valvetronic control unit
Furthermore, the N46 was now fuel-regulated over its predecessor in full-load operation via the lambda sensors. This reduced fuel consumption and improved exhaust gas levels, carbon monoxide (CO), hydrocarbon (HC), nitrogen oxide (NO x ) levels , and most importantly, benzene , which has been shown to cause cancer in full-load operation .
2006, the N46 was again modified (u. A. At the DME Bosch MV17.4.6) and offered as N46N. It is sold in some markets where increased sulfur concentration in the fuel makes it impossible to use the N43 .
In addition, the engine is used without Valvetronic as N45 with 1.6 and 2.0 liters.
The N42 serves as the basis for the smaller N45 engine (which does not have valvetronic).
In 2007, the N46's successor - the N43 - was introduced. However, the direct-injected N43 was not sold in countries with high-sulfur fuel, so the N46N continued to be produced alongside the N43. The N46N continued production until 2015, when the last N46 models were replaced by the turbocharged N13.
Models
Engine | Displacement | Power | Torque | Redline | Year |
---|---|---|---|---|---|
N46B18 | 1,796 cc | 85 kW (116 PS; 114 hp) @ 5500 | 175 N·m (129 lb·ft) @ 3750 | 6500 | 2004 |
N46B20U1 | 1,995 cc | 95 kW (129 PS; 127 hp) @ 5750 | 180 N·m (133 lb·ft) @ 3250 | 6500 | 2004 |
N46B20U2 | 100 kW (136 PS; 134 hp) @ 5750 | 180 N·m (133 lb·ft) @ 3250 | 6500 | 2007 | |
N46B20O0 | 105 kW (143 PS; 141 hp) @ 6000 | 200 N·m (148 lb·ft) @ 3750 | 6500 | 2004 | |
N46B20O1 | 110 kW (150 PS; 148 hp) @ 6200 | 200 N·m (148 lb·ft) @ 3600 | 6500 | 2004 | |
110 kW (150 PS; 148 hp) @ 6200 | 200 N·m (148 lb·ft) @ 3750 | 6500 | 2004 | ||
N46NB20 | 115 kW (156 PS; 154 hp) @ 6400 | 200 N·m (148 lb·ft) @ 3600 | 6500 | 2007 |
N46B18
The N46B18 has a 1796 cc displacement and produces 85 kW (116 PS; 114 hp) and 175 Nm.
Applications:
- 2004-2005 E46 316i/316ti
- 1.8 liters (1796 cc), 85 kW (115 hp), 175 Nm.
N46B20U1
The N46B20U1 produces 95 kW (127 hp) and 180 N·m (133 lb·ft).
Applications:
- 2005-2007 E87 118i
- 2005-2007 E90/E91 318i
N46B20U2
The N46B20U2 produces 100 kW (134 hp) and 180 N·m (133 lb·ft). It was used instead of the N43 in countries with high-sulfur fuel.
Applications:
- 2007-2011 E81/E87 118i
- 2007-2013 E90 318i
N46B20O0
The N46B20O0 produces 105 kW (141 hp) and 200 N·m (148 lb·ft).
Applications:
- 2004-2006 E46 318i, 318Ci and 318ti
N46B20O1
The N46B20O1 produces 110 kW (148 hp) and 200 N·m (148 lb·ft). On models with secondary air injection, peak torque occurs at 3750 rpm instead of 3600 rpm.
BMW E83 X3 2.0i Engine specification
Engine Size | 1995cc |
---|---|
Cylinders | 4 |
Valves | 16 |
Fuel Type | Petrol |
Power | 147 bhp |
---|---|
Top Speed | 123 mph |
0-60 mph | 11.1 secs |
Torque | 200 Nm, 148 ft-lb |
CO2 Emissions | 223 g/km |
Euro Emissions Standard | 4 |
Applications:
- 2004-2007 E83 X3 2.0i
- 2005-2008 E85 Z4 2.0i
- 2004-2007 E87 120i
- 2005-2007 E90/E91 320i
N46NB20
The N46NB20 produces 115 kW (154 hp) and 200 N·m (148 lb·ft). It was used instead of the N43 in countries with high-sulfur fuel.
Applications:
- 2007-2011 E81/E82/E87/E88 120i
- 2007-2013 E90/E91/E92/E93 320i
- 2007-2010 E60 520i
- 2009-2015 E84 X1 sDrive18i / xDrive18i
- 2007-2010 E83 X3 2.0i
Technical
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BMW N46 Engine Technical details and specifications (2004-2015)
1.8L
No. of cylinders 4/DOHC
Capacity 1796cc
Compression ratio 10,2:1
Firing order 1-3-4-2
Minimum octane rating 95 RON
Ignition/Fuel system Make Bosch Type Motronic ME9.2
Air metering Type Mass
Combined ignition and fuel ECM
Fuel pump delivery pressure 3,5bar
Oil pressure 4,0 bar/6,0 rpm
Radiator cap 1,8-2,1 bar© Motor car History
Service
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BMW N46 Engine Service Guide (2004-2015)
1.8L
Engine oil grade - normal/moderate climate 0W/40SAE Synthetic or 5W/30 Synthetic
Engine oil grade - cold climate 0W/40SAE Synthetic
Engine oil grade - hot climate 5W/40SAE Synthetic
Engine oil with filter 4,25 litresTightening torques
Cylinder head Renew bolts
Stage 1 Tighten 15 Nm
Stage 2 Tighten 30 Nm
Stage 3 Tighten 90°
Stage 4 Tighten 90°© Motor car History
Maintenance
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