how to fix P0301 misfire code in BMW 5 Series F10/F11 (2010-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down completely.

2. Replace Spark Plug

1. Locate the spark plug for cylinder 1 (usually under the engine cover).
2. Remove the engine cover (if applicable) using a socket set.
3. Use a spark plug socket to remove the old spark plug.
4. Inspect the old spark plug's condition; replace if fouled or worn.
5. Install the new spark plug, ensuring it is gapped correctly to manufacturer specifications (typically around 0.030-0.035 inches).
6. Torque the spark plug to the manufacturer's specified value (generally around 18-22 ft-lbs).

3. Inspect/Replace Ignition Coil

1. Disconnect the electrical connector from the ignition coil for cylinder 1.
2. Remove the ignition coil using a socket set.
3. Inspect the ignition coil for any signs of damage or failure.
4. If necessary, install a new ignition coil, ensuring it is seated properly.
5. Reconnect the ignition coil electrical connector.

4. Check Fuel Injector

1. Locate the fuel injector for cylinder 1.
2. Disconnect the electrical connector from the fuel injector.
3. Use a multimeter to check the injector for proper resistance (typically 12-16 ohms).
4. If faulty, replace the fuel injector by removing it from the fuel rail.
5. Install the new fuel injector and reconnect the electrical connector.

5. Conduct Compression Test (if needed)

1. Remove the spark plug from cylinder 1.
2. Insert the compression tester into the spark plug hole.
3. Crank the engine for several seconds and record the compression reading.
4. Compare the reading to the manufacturer's specifications (usually around 140-200 psi).
5. If low, further diagnostics may be needed to check for valve or piston issues.