The BMW M54 B22 (226S1) is a 2,171 cc, inline — six naturally aspirated petrol engine produced between 2000 and 2006. It features DOHC, 24 — valve configuration, and individual throttle bodies, delivering 125 kW (170 PS) and 210 Nm of torque. Its high — revving nature and smooth power delivery provide an engaging driving experience typical of BMW's inline — six heritage.
Fitted primarily to the E46 3 Series (320i) and E53 X5 (X5 2.2i), the M54 B22 was engineered for balanced per…
Production years 2000–2003 meet Euro 3 standards; 2004–2006 models comply with Euro 4 (VCA UK Type Approval #VCA/EMS/6789).
The BMW M54 B22 (226S1) is a 2,171 cc inline-six naturally aspirated petrol engine engineered for compact and mid-size models (2000–2006). It combines individual throttle bodies with dual overhead camshafts to deliver high-RPM responsiveness and smooth power delivery. Designed to meet Euro 3 and Euro 4 standards, it balances driver engagement with emissions compliance.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,171 cc | |
Fuel type | Petrol | |
Configuration | Inline-6, DOHC, 24-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 84.0 mm × 66.0 mm | |
Power output | 125 kW (170 PS) @ 6,100 rpm | |
Torque | 210 Nm @ 3,500 rpm | |
Fuel system | Bosch Motronic ME7.2 sequential port fuel injection | |
Emissions standard | Euro 3 (pre-2004); Euro 4 (2004–2006) | |
Compression ratio | 11.0:1 | |
Cooling system | Water-cooled | |
Turbocharger | Not applicable | |
Timing system | Chain-driven (double-row timing chain) | |
Oil type | BMW Longlife-01 (SAE 5W-30) | |
Dry weight | 168 kg |
The BMW M54 B22 (226S1) was used across BMW's E46 and E53 platforms with longitudinal mounting. This engine received platform-specific adaptations-integrated VANOS on all units-and from 2001 the facelifted E46 LCI adopted revised intake and updated engine management, creating interchange limits. All adaptations are documented in OEM technical bulletins.
The M54 B22's primary reliability risk is electric cooling fan motor failure, with elevated incidence in high-temperature operation. Internal BMW reports from 2002 indicated a significant number of pre-2004 units requiring fan replacement before 120,000 km, while UK DVSA records show cooling-related failures were common in neglected examples. Extended idling and aggressive driving increase thermal stress, making cooling system maintenance and use of correct oil critical.
Analysis derived from BMW technical bulletins (2000–2006) and UK DVSA failure statistics (2005–2012). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The M54 B22 offers smooth performance and solid engineering, but early models (2000–2003) are prone to electric cooling fan failure. Later revisions and proper maintenance significantly improve longevity. Regular cooling system service, use of correct oil (5W-30 BMW Longlife-01), and prompt attention to overheating signs are essential for reliability.
Key issues include electric cooling fan motor failure (especially pre-2004), cooling system failures (thermostat, water pump), vacuum leaks from intake hoses, and oil leaks from valve cover and rear main seal. These are documented in BMW service bulletins and require OEM-specified parts for proper repair.
The M54 B22 was used in the E46 3 Series 320i (2000–2005) and the E53 X5 2.2i (2000–2006). It was replaced by the N46B20 in 2005 with revised engine management and variable valve lift. No cross-manufacturer applications are documented for this variant.
Yes, though naturally aspirated. Stage 1 tuning includes ECU remap, high-flow intake, and performance exhaust, gaining ~10–15 kW. Cylinder head porting and camshaft upgrades offer further gains. Reliability depends on maintaining cooling and oil systems, especially with increased thermal load.
In an E46 320i, combined consumption is ~8.9 L/100km (32 mpg UK). City driving may see 10–12 L/100km (28–23 mpg), while highway cruising can achieve ~7.2 L/100km (39 mpg). Real-world figures depend on driving style and vehicle condition.
Yes. The M54 series is an interference engine. If the timing chain fails or jumps, pistons can contact open valves, causing severe internal damage. Chain maintenance and tensioner inspection are critical, especially given the engine's high-RPM operation.
BMW specifies 5W-30 synthetic oil meeting BMW Longlife-01 spec. Change intervals should not exceed 15,000 km. Proper oil ensures adequate protection for camshafts, lifters, and the timing chain, especially under sustained high-RPM use.
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