how to resolve P0301 misfire code in BMW X5 G05 (2019-2024)?

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, compression tester, fuel injector tester, multimeter.
• Ensure the vehicle is parked on a level surface, and the engine is cool.
• Disconnect the negative battery terminal for safety.

2. Inspect and Replace Spark Plug

1. Remove the engine cover if applicable using a socket set.
2. Disconnect the ignition coil connector from cylinder 1.
3. Remove the ignition coil by unscrewing it and pulling it out.
4. Remove the spark plug using a spark plug socket.
5. Inspect the spark plug for fouling or wear. Replace if necessary with a spark plug specified for the vehicle (refer to the owner’s manual for specifications).
6. Install the new spark plug, torque to specifications (usually around 20 Nm).
7. Reinstall the ignition coil and reconnect the connector.

3. Test and Replace Ignition Coil

1. If the spark plug is in good condition, test the ignition coil using a multimeter.
2. Measure the resistance across the ignition coil terminals; compare with specifications (typically 0.5 - 1.5 ohms).
3. If the ignition coil is faulty, replace it with a new one.
4. Reconnect all components.

4. Inspect and Test Fuel Injector

1. Use a fuel injector tester to check the operation of the injector for cylinder 1.
2. If the injector is not functioning properly, remove it by disconnecting the fuel rail and electrical connector.
3. Replace the faulty fuel injector with a compatible part.
4. Reinstall the fuel rail and ensure all connections are secure.

5. Check for Vacuum Leaks

1. Inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
2. Use a smoke machine or carburetor cleaner to check for leaks while the engine is running.
3. Repair or replace any damaged hoses.