Engine code
N46 · 1.8 and 2.0 liter · 4-cylinder with Valvetronic · 2003-2015 in BMW's parts catalog · 316i, 318i, 320i, 118i, 120i, X3 2.0i, Z4 2.0i, X1 18i
The N46 is the redesigned N42: a 4-cylinder petrol engine with double VANOS and Valvetronic, sold as the 1.8 liter N46B18 and the 2.0 liter N46B20. It went into the E46, E87, E90 and E91 and, in the higher power stage, into the E83 X3 and E85 Z4. A technical update, the N46TU2, followed from 03/2007. The N46 was not sold in US-market BMWs, per BMW's own vehicle lists (data to December 2019), so this is a short guide.
This guide only states what BMW's own documents establish. Ownership opinions, failure rates, costs and tuning potential are marked as not established.
N46 At a Glance
| Question | Practical answer |
|---|---|
| Where you find it | E46 316i, 316ti, 318i, 318Ci and 318ti; E81, E87 and E88 118i and 120i; E82 120i; E90 and E91 318i and 320i; E92 and E93 320i; E83 X3 2.0i; E85 Z4 2.0i; E60 520i and 520Li; E84 X1 18i. |
| Catalog window | BMW's parts catalog lists catalog dates from 03/2003 to 06/2015. BMW's service overviews give later start dates for some cars (the 118i from 12/2004, the X3 from mid-2005), so treat start years as approximate. |
| Sold in US-market BMWs | Not sold in US-market BMWs, per BMW's own vehicle lists (data to December 2019). All 132 N46 and N46N vehicle types BMW lists are for other markets, mainly the Europe catalog. |
| Engine sizes | 1.8 liter N46B18 and 2.0 liter N46B20, the 2.0 in a lower (uL) and a higher (oL) power stage |
| Factory output | E46: N46B18 85 kW and 180 Nm, N46B20 105 kW and 200 Nm. E87, E90, E91: N46B20uL 95 kW and 180 Nm, N46B20oL 110 kW and 200 Nm. E83 and E85: N46B20oL 110 kW and 200 Nm. |
| Valvetronic | Yes. On the N46 BMW folded the Valvetronic control into the main engine computer. |
| Later version | N46TU2, introduced 03/2007, with more output than the N46. Not used in the E83 or E85. |
| Engine oil | 4.25 liters with a new filter. Check the owner's manual for the grade; BMW's current oil suitability list includes the N46. |
| Reliability, cost to own, power potential | Not established yet. We are still researching this engine. |
Technical Specifications
| Specification | Detail |
|---|---|
| Cylinders | 4, petrol |
| Displacement | N46B18: 1,796 cc. N46B20: 1,995 cc. |
| Bore x stroke | N46B18: 84 x 81 mm. N46B20: 84 x 90 mm. |
| Compression ratio | E46: N46B18 10.2:1, N46B20 10.0:1. E87, E90, E91 N46B20: 10.5:1. E83 and E85 N46B20oL: 10.5:1. |
| Maximum engine speed | 6,500 rpm, constant speed 6,300 rpm (E46 workshop data) |
| Valvetrain | Double VANOS and Valvetronic. Differential air intake control (DISA) on the N46B20oL only. |
| Engine management | Digital engine electronics MEV 9.2 with the Valvetronic control integrated, and a DME control unit with 2 connectors |
| Secondary air system | Fitted on the E46, E83 and E85 versions. Not fitted on the E81, E87, E90 and E91, where the catalytic converter sits close to the engine. |
| Emissions | Euro 4 |
| Engine oil capacity | 4.25 liters with filter change |
| Oil level check | No dipstick on the E87, E90 and E91; electronic level check in the instrument cluster menu |
| Air mass meter | None on the E87, E90 and E91 N46 cars with a catalytic converter; reintroduced from 06/2006 for countries with inadequate fuel quality |
| Coolant, firing order | Not established yet |
Known Failure Points and Service Items
Not established yet. We found no BMW recall, technical bulletin or training document that names a specific N46 defect. The US recall database does not apply because the engine was not sold in the US.
Reliability Verdict, Power Potential, Cost of Ownership
Not established yet. We are still researching this engine.
Common Questions
What BMW has the N46 engine?
BMW's parts catalog lists the N46 in the E46 316i, 318i and related models, the E87 118i and 120i, the E90 and E91 318i and 320i, the E83 X3 2.0i, the E85 Z4 2.0i and the E84 X1 18i. It was not sold in US-market BMWs, per BMW's own vehicle lists (data to December 2019).
Does the N46 have Valvetronic?
Yes. BMW's engine data lists double VANOS and Valvetronic for the N46B18 and N46B20, and the Valvetronic control is inside the engine computer.
How much power does an N46 make?
BMW lists 85 kW for the N46B18 and 105 kW for the N46B20 in the E46, and 95 kW or 110 kW for the 2.0 liter in the E87, E90 and E91 depending on the power stage.
How much oil does an N46 take?
BMW's workshop data gives 4.25 liters for an oil change with a new filter element.
Sources
- BMW service documentation, engine control for N45 and N46 (11 01 04 (068)), with the engine-specific data enclosure for the N45 and N46.
- BMW E87 1 Series overview and the exhaust system overview for N40, N42, N45 and N46.
- BMW workshop technical data for the N46B18 and N46B20, group 11: engine in general, oil supply.
- BMW parts catalog, data date 12 December 2019 (vehicle types, build dates).
- BMW oil suitability list for BMW Group engines, edition 09/2025.
