why does my BMW 5 Series G30/G31 (2017-2024) check engine light keep coming on

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 ensure safety during repairs.

2. Address Fault Codes

• Use the OBD-II scanner to clear existing fault codes after repairs.
• If the same code reappears, investigate that specific area further (e.g., if a P0300 code shows, check for misfires).

3. Inspect and Replace Components

Spark Plugs and Ignition Coils

• Remove the engine cover (if applicable).
• Disconnect the ignition coil connectors and remove the coils using a socket wrench.
• Replace spark plugs with the manufacturer-recommended type and torque to specification (typically 18-22 lb-ft).
• Reinstall ignition coils and reconnect connectors.

Mass Airflow Sensor (MAF)

• Locate the MAF sensor on the intake duct.
• Disconnect the electrical connector and unscrew the sensor from the intake.
• Clean the MAF sensor with MAF cleaner and reinstall, ensuring a secure fit.

Throttle Position Sensor (TPS)

• Locate the TPS on the throttle body.
• Disconnect the electrical connector and unbolt the sensor.
• Install a new TPS and torque to the manufacturer's specifications. Reconnect the electrical connector.

4. Fuel System Check

• Check fuel pump operation by turning the ignition to the "on" position and listening for the pump.
• Use a fuel pressure gauge to assess fuel pressure against specifications (usually between 40-60 psi for most BMWs).
• Replace the fuel filter if clogged or the fuel pump if it fails to deliver proper pressure.