The 2003 BMW 325i uses a 2.5-liter inline-6 engine from BMW’s M54 family, known as the M54B25. In most markets it produces about 184 horsepower and 175 lb-ft of torque.
Engine basics and designation
The 2003 325i is powered by the M54B25 engine, a member of BMW's M54 inline-6 family. It features dual overhead cams and variable valve timing (VANOS), delivering smooth and refined performance that characterizes BMW’s six-cylinder engines from that era.
Key specifications include:
- Engine code: M54B25
- Displacement: 2,494 cc (2.5 L)
- Configuration: Inline-6 (I-6)
- Valvetrain: DOHC with VANOS
- Fuel system: Sequential multi-point fuel injection
- Power: ~184 hp (137 kW) @ ~6,000 rpm
- Torque: ~175 lb-ft (237 Nm) @ ~3,500 rpm
Note that power and torque figures can vary slightly by market and model year due to exhaust tuning and emissions equipment.
Position in the 3-series lineup
In the E46 generation (1998–2006), the 325i sits in the mid-range of the petrol lineup, above smaller-displacement variants and below the 330i with its larger 3.0-liter engine. The 325i is available with rear-wheel drive as standard, with some markets offering all-wheel drive in the 325xi variant. The engine is shared between these trim levels, providing consistent performance characteristics across configurations.
Markets and driveline options
In the United States and many other markets, the 325i used the M54B25 engine paired with either a 5-speed manual or a 5-speed automatic transmission. The all-wheel-drive version, the 325xi, uses the same engine but with a drivetrain tuned for additional traction.
Summary
The 2003 BMW 325i’s core powerplant is the M54B25 2.5-liter inline-6, featuring DOHC with VANOS and sequential multi-point fuel injection. It delivers roughly 184 horsepower and 175 lb-ft of torque, and is offered with both manual and automatic transmissions depending on market and trim.