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BMW N45B16 Engine (Design, Specs & Reliability)

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Last Updated on: 16th November 2023, 02:45 am

The BMW N45B16 is a small 1.6-liter engine which produces 116 hp and 150 nm of torque and was created in 2004.

In this article, we’ll be discussing the design, problems and reliability of the BMW N45B16 engine.


The new engine features a new piston, new connecting rods, and a new crankshaft with a shortened piston stroke (it was 81, now 72 mm).

Additionally, the N45B16 does not use the Valvetronic valve lift technology.

Bosch ME 9.2 engine management system Since 2007, the engine has undergone updates, been given a new Bosch ME17.4.5 control unit, and had the moniker N45NB16 appended.

On BMW vehicles a 16i, this engine was used. A 2-liter sports variant of this engine, the N45B20S, was also developed as part of the limited-edition N45 series.

BMW N45B16 Engine

Engine Specs

  • Production years: 2004-2011
  • Displacement: 1596 cc
  • Fuel system: injector
  • Power output: 116 hp @ 6000 rpm
  • Torque output: 150 nm @ 4300 rpm
  • Block material: aluminum R4
  • Cylinder head: aluminum 16v
  • Bore: 84 mm
  • Stroke: 72 mm
  • Compression ratio: 10.5:1
  • Features: Bosch ME 9.2 (N45B16), Bosch ME 17.4.5 (N45NB16)
  • Hydraulic lifters:yes
  • Timing drive: chain
  • Phase regulator: double VANOS
  • Turbocharging: no
  • Recommended engine oil: 5W-30
  • Engine oil capacity: 4.5 litres
  • Fuel type: Petrol
  • Euro standards: EURO 4/5
  • Fuel consumption, L/100 km (for 116i E87): city 8.8, highway 4.9, combined 6.2
  • Engine lifespan: ~320 000 km

Problems & Reliability

It should be noted that this series’ power unit has the potential to display fuel mixture detonation. The low quality of the oil or gasoline is the cause.

The oil must only be of the brand and model that BMW recommends. Otherwise, there is a higher chance of creating significant issues; even a significant overhaul is probable.


The majority of the time, issues are concealed by a broken timing chain tensioner.

In addition, the chains in general have a short lifespan and are easily stretched after the vehicle has driven roughly 100,000 km. Replacement is necessary.


The Vanos system might be malfunctioning and causing the vibrating at idle. It will thus need to be examined and cleaned. Possible replacement in its entirety.


BMW N45B16 Engine
BMW N45B16 Engine
  • Andy Lewin

    Andy Lewin is a senior mechanic, ASE qualified master technician, and an experienced automotive engineer. He's passionate about serving the automotive community with the highest-quality and trustworthy information on all things automotive. He loves to write about car repairs, maintenance, car modifications and tuning, faults, and much more.

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