BMW 528i 2004-2010 Fuel System Specifications

• Use premium unleaded gasoline with an octane rating of 91 AKI (Anti-Knock Index) or higher.
• Minimum octane rating of 89 AKI is acceptable but may reduce performance.
• Avoid using gasoline with more than 10% ethanol (E10).
• Do not use diesel or leaded gasoline.

• BMW recommends using fuel additives only if approved by BMW.
• Avoid using aftermarket additives that contain metal compounds.
• Use additives to clean fuel injectors if necessary, but sparingly.
• Ensure additives are compatible with the fuel system components.

Note: Using unapproved additives may void the vehicle warranty.

• Electric fuel pump with a pressure range of 3.5 to 5.5 bar (50.8 to 79.8 psi).
• Fuel flow rate of 120 liters per hour (31.7 gallons per hour).
• Located inside the fuel tank for cooling and noise reduction.
• Equipped with a fuel level sensor for accurate fuel gauge readings.

• Direct fuel injection system with solenoid-operated injectors.
• Injector flow rate of 200 cc/min at 3.0 bar (43.5 psi).
• Injector spray pattern optimized for efficient combustion.
• Designed to operate at a voltage of 12V.

• Normal operating pressure: 3.5 to 5.5 bar (50.8 to 79.8 psi).
• Pressure measured at the fuel rail using a pressure gauge.
• Low pressure may indicate a failing fuel pump or clogged filter.
• High pressure may suggest a faulty pressure regulator.

• Use a calibrated fuel pressure gauge for accurate measurements.
• Test pressure with the engine running and at idle.
• Compare readings to factory specifications for diagnosis.
• Inspect fuel lines and connections for leaks during testing.

Note: Always relieve fuel system pressure before servicing to avoid injury.

• City driving: 18 mpg (13.1 L/100 km).
• Highway driving: 28 mpg (8.4 L/100 km).
• Combined driving: 22 mpg (10.7 L/100 km).
• Actual mileage may vary based on driving conditions.

• Maintain proper tire pressure for reduced rolling resistance.
• Avoid aggressive acceleration and braking.
• Use cruise control on highways to maintain consistent speed.
• Regularly replace air filters and spark plugs for optimal combustion.