why does my BMW 3 Series F30/F31 (2012-2019) smell like gas when I start it?

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the battery to prevent any electrical hazards.

2. Inspect and Replace Fuel Lines (if damaged)

• Tools Required: Socket set, wrenches, fuel line removal tool.
• Remove any covers blocking access to the fuel lines.
• Inspect each fuel line for cracks or leaks.
• If damage is found, use the fuel line removal tool to disconnect the damaged line.
• Install the new fuel line, ensuring all connections are tight and secure.

3. Test Fuel Injectors

• Tools Required: Fuel pressure gauge, multimeter.
• Reconnect the battery.
• Attach the fuel pressure gauge to the fuel rail.
• Turn the ignition to the ON position (without starting) to check the fuel pressure.
• If the pressure is low or fluctuating, test each injector with a multimeter for proper resistance.
• Replace any faulty injectors.

4. Examine and Replace Fuel Cap

• Tools Required: None (if it's a simple cap replacement).
• Inspect the fuel cap for cracks or a worn rubber seal.
• If damaged, replace the fuel cap with a new one ensuring it clicks securely when closed.

5. Check Fuel Pressure Regulator

• Tools Required: Fuel pressure gauge.
• Disconnect the vacuum line from the fuel pressure regulator.
• Connect the fuel pressure gauge and start the engine.
• Monitor the pressure; it should be within the manufacturer's specifications.
• If the pressure is out of range, replace the fuel pressure regulator.