how to diagnose P0302 code on Ford F-150 13th Generation (2015-2020)

Solution

1. Preparation

• Tools Required: OBD-II scanner, spark plug socket, torque wrench, multimeter, compression tester, fuel injector cleaning kit.
• Disconnect the negative battery cable to ensure safety during repairs.

2. Replace Spark Plug

• Remove the engine cover (if applicable).
• Use the spark plug socket to remove the spark plug from cylinder 2.
• Inspect the old spark plug for wear or damage. Clean the cylinder head area of debris.
• Install a new spark plug with the correct gap (refer to the owner's manual for specifications).
• Torque the spark plug to the manufacturer's specifications (typically around 13 lb-ft).

3. Test and Replace Ignition Coil

• Remove the ignition coil for cylinder 2 by unbolting it and disconnecting the electrical connector.
• Swap the ignition coil with another cylinder (e.g., cylinder 1).
• Clear the error codes and run the engine to see if the P0302 code returns to cylinder 2 or if it moves to the cylinder where the coil was placed.
• If the code moves, replace the ignition coil with a new one.

4. Inspect and Clean Fuel Injector

• Remove the fuel injector for cylinder 2 by disconnecting the electrical connector and loosening the retaining clips.
• Test the injector with a multimeter to ensure it has the correct resistance (typically 12-16 ohms).
• If the injector is faulty, replace it with a new one. If it’s functional, clean it using a fuel injector cleaning kit and reinstall.

5. Perform Compression Test

• Remove spark plugs for all cylinders for a more accurate reading and connect the compression tester to cylinder 2.
• Crank the engine for a few seconds to get a reading. The compression should be within the manufacturer’s specified range (typically 120-180 psi).
• If compression is low, investigate potential causes such as valve issues or head gasket failure.