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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the engine is cool and disconnect the negative battery terminal.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench.
• Remove the ignition coil from cylinder 1 by unscrewing the bolts and lifting it out.
• Remove the spark plug using a spark plug socket.
• Inspect the spark plug for signs of fouling or damage.
• If needed, replace with a new spark plug (specify the part number according to manufacturer specifications).
• Reinstall the spark plug and torque it to the manufacturer’s specifications (typically around 18-22 ft-lbs).

3. Inspect and Replace Ignition Coil

• If the spark plug is in good condition but the misfire persists, check the ignition coil.
• Tools Required: Socket set, multimeter (for testing).
• Remove the ignition coil from cylinder 1 and test for resistance using a multimeter (check manufacturer specifications).
• If the coil is faulty, replace it with a new one.
• Reinstall the ignition coil and ensure it is securely fastened.

4. Inspect and Clean Fuel Injector

• If the ignition system checks out, inspect the fuel injector.
• Tools Required: Fuel injector cleaning kit (if necessary).
• Disconnect the fuel injector connector and remove it from the rail.
• Inspect for clogs or leaks; clean the injector or replace as necessary.
• Reinstall the fuel injector and reconnect the wiring.

5. Compression Test

• If misfire continues, conduct a compression test.
• Tools Required: Compression gauge.
• Remove the spark plug, insert the compression gauge into cylinder 1, and crank the engine.
• Compare the compression reading with specifications (around 140-200 psi).
• If the compression is low, further investigation for mechanical issues (valve problems, piston rings) may be required.