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BMW N54 engine
JK N54B30.jpg
Manufacturer BMW
Production 2006–2016
Configuration Straight-6
Valvetrain DOHC
Turbocharger Twin-Turbo
Fuel system Direct injection
Predecessor None
Successor BMW N55

The BMW N54 is a turbocharged straight-6 petrol engine that was produced from 2006 to 2016.[1] It is BMW's first mass-produced turbocharged petrol engine, and BMW's first turbocharged petrol engine since the limited-production M106 was discontinued in 1986. The N54 debuted at the 2006 Geneva Motor Show and was launched in late 2006 in the E92 335i.

Following the introduction of its N55 successor in 2009, the N54 began to be phased out. The final model powered by the N54 is the E89 Z4 sDrive 35is, which produced until 2016.

The N54 has won five straight International Engine of the Year awards,[2] and three straight Ward's 10 Best Engines awards.[3]

There is no M version of the N54, however a high-output version of the N54 is used in the 1 Series M Coupe.


The N54 was produced alongside the naturally aspirated N53 engine, and both engines feature direct injection, variable valve timing on both camshafts (called dual VANOS by BMW), an open-deck engine block,[4] and an electric water pump.[5][6][7] However, the N54 is based on the older M54 naturally aspirated engine.[8] and therefore uses an aluminium engine block (instead of the magnesium alloy used by the N53) and has a capacity of 2,979 cc (182 cu in) and does not have variable valve lift (called valvetronic by BMW).

Turbocharging is a key difference between the N54 and BMW's previous straight-six engines. The N54 has two small low-pressure turbochargers to minimise turbo lag. The boost pressure is 8.8 psi and an air-to-air intercooler is used. Compared with the naturally aspirated N52 engine (which the N54 replaced in some North American models), the N54 produces an additional 45 hp (34 kW) and 80 lb⋅ft (108 N⋅m).[9] Car & Driver noted the N54 had minimal turbo lag and "in feel and sound the twin-turbo could pass for naturally aspirated".[10] The N54-engined F01 740i was also praised for its linear power delivery.[11]

BMW's term for turbocharging is "TwinPower Turbo",[12] which has also been applied to the N55, which uses a single twin-scroll turbocharger (as well as Valvetronic variable valve lift). Initial versions of the N55 produced the same peak power and torque as the N54, although the N55 produced peak torque 200 rpm earlier.[13] Initially, the high-output versions of the N54 (such as used in the 2009 F01 740i[14][15]) were more powerful than the N55. However, from 2016 onwards, more powerful versions of the N55 became available.[16]

The engine's direct injection system uses piezo injectors, as per the naturally-aspirated N53. The N55 engine uses solenoid-type injectors, because the piezo injectors are more expensive and not reaching their full potential to obtain the "lean burn" benefit.[17] BMW's trademark for direct injection, regardless of type, is known as "High Precision Injection".[18]

Effects on vehicle handling[edit]

Comparing the N54-engined E60 535i with the 550i (using a 4.8 litre naturally aspirated V8 engine), Car and Driver noted "As torquey as the 550i is, though, it is only marginally quicker than the 535i, and as the road bent deeper into the mountains, we noticed the additional weight in the nose more and more".[19] Similarly, the handling of the N54-engined F01 740i was described by Edmunds as "tossable", compared to the twin-turbo V12-engined 760Li model, although the 760Li was faster in a straight line.[20]


As per the 3.0 litre version of the naturally aspirated BMW M54, all models have a bore of 84 mm (3.3 in), a stroke of 89.6 mm (3.5 in), a capacity of 2,979 cc (181.8 cu in) and a compression ratio of 10.2:1.

Engine Power Torque Redline Year
N54B30 225 kW (306 PS)
@ 5800
400 N⋅m (300 lb⋅ft)
@ 1400-5000
7000 2006-2010
240 kW (330 PS)
@ 5800
450 N⋅m (330 lb⋅ft)
@ 1500-4500
7000 2008-2013
250 kW (340 PS)
@ 5900
450 N⋅m (330 lb⋅ft)
@ 1500-4500
7000 2011-2016

225 kW version[edit]

The initial version of the N54 is officially rated at 200 kW (270 hp) and 400 N·m.[21] However, these figures are considered to be under-rated,[22] and independent testing has resulted in estimates of 311 hp (232 kW) and 311 lb·ft/422 N·m.[23]


240 kW version[edit]

A variant of the N54B30 with higher power and torque (but a slight reduction in low rpm torque) is used in the F01 740i[14] and E92 335is.


250 kW version[edit]

The most powerful version of the N54 is found in the E82 1 Series M Coupe and the E89 Z4 sDrive 35is.


High-Pressure Fuel Pump failures[edit]

In the United States, many N54 engines experienced failures of the High Pressure Fuel Pump (HPFP), resulting a class action lawsuit, a voluntary recall and an extended warranty for the HPFP.

Failure of the HPFP can cause the engine to suddenly stop functioning, which has caused several near-misses on highways.[30] BMW was aware of HPFP problems, describing them in internal Technical Service Bulletins as "driveability problems".[30]

In April 2009, a class action suit was filed against BMW in connection with HPFP failures.[31][32] BMW settled the suit in June 2010. On 26 October 2010, following an ABC News story about HPFP failures,[33] BMW announced a recall of vehicles with the pump in question from manufacturing years 2007-2010.[34][35] The recall was applied to 130,000 cars, resulting in the replacement of the HPFP in approximately 40,000 of these cars.[36]

In the United States, the warranty period for the HPFP was increased to 10 years and 120,000 mi (190,000 km).[37]

On some cars, the HPFP was replaced multiple times without resolving the issue, potentially leading to the car being refunded under the Lemon Laws in some states.[38]

Extended warranty in the United States[edit]

The High Pressure Fuel Pump issue caused BMW North America to extend the warranty for this pump to 10 years or 120,000 mi (190,000 km).

The warranty period for the fuel injectors was also increased, to 10 years or 120,000 mi (190,000 km).[39][40] An updated design for the fuel injectors was also introduced.[41][42]

Due to problems with rattling wastegates caused by premature bushing wear,[43][44] BMW extended the warranty period for wastegate-related issues to 8 years or 82,000 mi (130,000 km).[45]

These warranty extensions only apply to the United States.

See also[edit]


  1. ^ "Direct Injection, Turbo Pay Off For BMW". 
  2. ^ "BMW takes home 4 awards from International Engine of the Year competition - N54 and S65 continue dominance". 
  3. ^ "BMW's Newest I-6 Better, Not Bigge". 
  4. ^ "BMW N54 engine". Retrieved 8 December 2017. 
  5. ^ "Motor Engine: BMW N54 inline 6 twin turbo". 
  6. ^ "Engine Guide BMW N54/N55". 
  7. ^ "5' F10 530i Waterpump - Thermostat". Retrieved 8 December 2017. 
  8. ^ "BMW N54 and N55 Six Cylinder Turbocharged Engines". 
  9. ^ "2008 BMW 5-series - First Drive Review". Retrieved 5 January 2017. 
  10. ^ "2007 BMW 335i Coupe - Road Test". 
  11. ^ "2012 BMW 740i Sedan - Editors' Notebook". Retrieved 5 January 2017. 
  12. ^ "BMW EfficientDynamics: Petrol engines with BMW TwinPower Turbo Technology". 
  13. ^ "2011 BMW 335i Sedan". Archived from the original on 10 March 2016. 
  14. ^ a b "2011 BMW 740i / 740Li - First Drive Review". Archived from the original on 16 September 2010. 
  15. ^ "New BMW 7-Series F01 Specifications and Photos". 
  16. ^ "2017 BMW X4 M40i Instrumented Test". Retrieved 10 December 2017. 
  17. ^ "BMW's Newest I-6 Better, Not Bigger". 
  18. ^ "BMW Technology Guide: High Precision Injection". 
  19. ^ "V-8 with Extra Weight- 2008 BMW 5-series". Archived from the original on 14 January 2016. 
  20. ^ "2011 BMW 740i First Drive". Edmunds. Retrieved 5 January 2017. 
  21. ^ "The latest BMW engine: N55 - found in the BMW 5 Series GT". 
  22. ^ "First Drive Review - 2011 BMW 335i Sedan". Retrieved 16 December 2017. 
  23. ^ "Press release- Performance Engine Software for BMW 335 Models" (PDF). Archived from the original (PDF) on 20 September 2010. 
  24. ^ "BMW 335i Coupe (2006) review". Retrieved 16 December 2017. 
  25. ^ "2009 BMW 5-series E61 phase-II (Touring) Wagon X (4WD) full range specs". Retrieved 16 December 2017. 
  26. ^ "2011 BMW 335is First Drive". Archived from the original on 21 September 2010. 
  27. ^ "2010 BMW 335is Coupé". 
  28. ^ "BMW 1-Series M Coupe Review". 
  29. ^ "Dyno-Tested: 2011 BMW 1 Series M Coupe". 
  30. ^ a b Cohan, Peter. "BMW's Engine Problems: A Safety Risk to Drivers – and the Company?". Retrieved 16 December 2017. 
  31. ^ "Kershaw, Cutter & Ratinoff takes on BMW in class action suit regarding defective HPFP". Retrieved 16 December 2017. 
  32. ^ "Jay Alan Morane vs BMW North America- April 10 2009". 
  33. ^ "ABC News airs big expose on BMW N54 engine problems, lawsuits". 
  34. ^ Morran, Chris (2010-10-26). "BMW Recalls 150,000 Cars Over Fuel Pump Failures". Consumerist. Retrieved 2011-06-22. 
  35. ^ Consumerist: BMW Recalls 150,000 Cars Over Fuel Pump Failures
  36. ^ "BMW Recalls Some Turbo-Charged Cars Following ABC News Investigation". Retrieved 16 December 2017. 
  37. ^ "High Pressure Fuel Pump for Turbo vehicles - BMW 335i, 335xi". Retrieved 16 December 2017. 
  38. ^ "What's the deal with all these Lemon/Buyback 335i's?". Retrieved 16 December 2017. 
  39. ^ "N54: The best Plugs, Injectors and Coils Thread". Retrieved 16 December 2017. 
  40. ^ "BMW Fuel Injector – Ext'd Warranty, Reimbursement". Retrieved 16 December 2017. 
  41. ^ "N63, N74, N54 Injector Update". Retrieved 16 December 2017. 
  42. ^ "N53 330i Powweerrr loss". Retrieved 16 December 2017. 
  43. ^ "BMW Turbo Upgrades For The Infamous N54". Retrieved 16 December 2017. 
  44. ^ "BMW 135i 335i 535i N54 Wastegate Rattle Fix". Retrieved 16 December 2017. 
  45. ^ "N54 Engine warranty extended to 8 Years/82,000 Miles (Wastegates Only)". 2012-08-16. Retrieved 4 October 2016.