why does my BMW X3 F25 (2011-2018) have low fuel efficiency suddenly

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working with electrical components.

2. Inspect and Clean the MAF Sensor

• Remove the MAF sensor from the intake duct.
• Use MAF cleaner to gently clean the sensor elements; do not touch them with your hands.
• Allow the cleaner to dry completely before reinstallation.

3. Replace the Fuel Filter

• Locate the fuel filter; refer to the vehicle's service manual for specific location.
• Relieve the fuel system pressure by removing the fuel pump relay and starting the engine until it stalls.
• Disconnect the fuel lines and remove the old filter.
• Install the new fuel filter, ensuring proper orientation and secure connections.

4. Clean or Replace Fuel Injectors

• Use a fuel injector cleaning kit or professional cleaning service to remove carbon buildup.
• If necessary, replace any faulty injectors with OEM or high-quality aftermarket parts.

5. Check and Replace the Air Filter

• Open the air filter housing and remove the old air filter.
• Inspect for dirt and debris; replace with a new air filter if needed.

6. Verify Tire Pressure

• Use a tire pressure gauge to check all tires.
• Inflate or deflate tires to the manufacturer's recommended pressure.