BMW N55 3.0 Turbo: Specs, Engine Codes & Maintenance
BMW · Engine information · U.S. & Canada
N55
3.0 turbo · Inline-six gasoline
One turbo, six cylinders, plenty of reach. The N55 pairs a twin-scroll turbocharger with variable valve lift for quick response and a broad torque band—from everyday 35i models to the original M2.
Architecture
- Layout
- Inline-six · DOHC · 24 valves
- Construction
- Aluminium block and cylinder head
- Bore × stroke
- 84.0 × 89.6 mm
- Displacement
- 2,979 cc
- Compression
- 10.2:1
- Valve control
- Timing chain · Double VANOS · Valvetronic III
Fuel, boost & control
- Injection
- Direct gasoline · solenoid injectors
- Fuel pressure
- Up to 200 bar
- Turbocharger
- Single twin-scroll · air-to-air intercooler
- Engine ECU
- Bosch MEVD17.2 family
- ECU variants
- MEVD17.2 / 17.2.6 / 17.2.G, by application
- Oil approval
- BMW Longlife-01 / model handbook specification
Engine controllers · Bosch MEVD17.2 variants
BMW calls the N55’s ECU the DME (Digital Motor Electronics). Bosch’s MEVD17.2, MEVD17.2.6 and MEVD17.2.G manage direct injection, ignition, boost, VANOS and Valvetronic. The DME mounts on the intake manifold, where intake air helps cool it.
| DME variant | N55 application examples | What to know |
|---|---|---|
| MEVD17.2 | Early 135i (E82/E88), 335i (E90/E92/E93) and X5 xDrive35i (E70) | Original N55 controller, used with pneumatic wastegate control. |
| MEVD17.2.6 | 335i F30: 2012–2013 Also 535i F10, X3 F25 and selected later E-series builds | Revised controller hardware; the F30 applications shown use a pneumatic wastegate (PWG). |
| MEVD17.2.G | 335i F30: 2014–2015 M235i F22: 2014–2016; F23: 2015–2016 M2 F87 / X4 M40i F26: 2016–2018 | Used in later 35i and performance N55 applications. The F30 applications shown use an electronic wastegate (EWG). |
PWG uses a vacuum actuator; EWG uses an electric actuator. Changeover dates vary by model. Confirm the fitted DME’s Bosch/BMW part number and software ID before programming or replacement; the suffixes are not automatically interchangeable.
Engine codes & factory output
| Engine variant | Application | Power | Torque |
|---|---|---|---|
| N55B30M0 | Standard 35i models | 300 hp | 300 lb-ft |
| N55B30O0 | M235i | 320 hp | 330 lb-ft |
| N55B30T0 | X4 M40i | 355 hp | 343 lb-ft |
| N55B30T0 | M2 | 365 hp | 343 lb-ft* |
*M2 overboost briefly raises torque to 369 lb-ft. Standard factory ratings; optional power packages are excluded. ECU hardware varies by build date—confirm the unit fitted to the vehicle.
Selected U.S. & Canadian vehicles
| BMW model | Chassis | Model years | Variant |
|---|---|---|---|
| 135i Coupe / Convertible | E82 / E88 | 2011–2013 | M0 |
| 335i / xDrive Sedan | E90 | 2011 | M0 |
| 335i Coupe / Convertible | E92 / E93 | 2011–2013 | M0 |
| 335i / xDrive Sedan | F30 | 2012–2015 | M0 |
| 435i Coupe / Convertible | F32 / F33 | 2014–2016 | M0 |
| 435i Gran Coupe | F36 | 2015–2016 | M0 |
| 535i / xDrive Sedan | F10 | 2011–2016 | M0 |
| X3 xDrive35i | F25 | 2011–2017 | M0 |
| X5 xDrive35i | E70 | 2011–2013 | M0 |
| X5 sDrive35i / xDrive35i | F15 | 2014–2018 | M0 |
| M235i Coupe | F22 | 2014–2016 | O0 |
| M235i Convertible | F23 | 2015–2016 | O0 |
| M2 (original model) | F87 | 2016–2018 | T0 |
| X4 M40i | F26 | 2016–2018 | T0 |
M0 / O0 / T0 refer to the full N55B30 engine codes above. Verify the VIN and engine identification at model-year transitions.
Common issues & key risks
Valve cover & PCV. The plastic cover, gasket and integrated breather are recurring repair points. Burning-oil smells, whistling or rough idle warrant leak and crankcase-pressure checks.
Oil-filter-housing gasket. Leaks can soak the auxiliary belt. Repair promptly: a displaced or shredded belt can create much more serious damage around the crankshaft seal.
Electric water pump. Pump failure can cause a loud fan, overheating warnings and reduced power. Check pump faults and thermostat operation; do not keep driving through a temperature warning.
Cracked charge pipe. The plastic pipe can split, causing a sudden hiss, lost boost and a drivetrain warning. Pressure-test the charge system before condemning the turbocharger.
Valvetronic wear. Actuator and eccentric-shaft wear can cause valve-lift faults or rough running. Check lubrication, mechanical movement and wiring as part of diagnosis.
Early high-pressure fuel pumps. Earlier versions can develop long cranking, low rail pressure or hesitation. Confirm the fitted pump version and measured fuel pressure before replacement.
Keep it consistent: use the oil approval specified for the vehicle, service it on time, and adjust intervals for demanding use. Build load progressively as the engine warms and investigate new leaks or warning lights early.
References
| Topic | Source |
|---|---|
| Engine design & specifications | BMW Technical Training — N55 Engine (ST916) |
| 300 hp applications | BMW 2011 3 Series · BMW 4 Series Coupe |
| Performance variants | BMW M235i · BMW M2 specifications · BMW X4 M40i |
| Cooling & boost diagnosis | BMW SI B01 13 21 — coolant pump · BMW SI B12 16 11 — boost pressure |
| Oil-leak assessment | BMW engine oil-leak diagnosis guidance |
| N55 recurring failures | FCP Euro · N55 technical guide |
| Valvetronic wear | FCP Euro · eccentric-shaft repair |
| Early fuel-pump faults | FCP Euro · HPFP symptoms |
| Engine photograph | BMW N55 engine 2013 — Avolutions, CC BY-SA 3.0, via Wikimedia Commons. Image unchanged. |
Technical bulletins apply to specified vehicles and conditions. Consult the vehicle handbook and current BMW service information for repair procedures.
