how to fix P0300 random misfire code on Toyota Camry Seventh Generation (2012-2017)

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to ensure safety during repairs.

Tools Required:

• OBD-II scanner
• Spark plug socket
• Torque wrench
• Fuel pressure gauge
• Smoke machine or carburetor cleaner
• Multimeter

2. Replace Spark Plugs

1. Remove the engine cover (if applicable) using a socket set.
2. Disconnect the ignition coils by unfastening the electrical connectors.
3. Remove the ignition coils using a socket wrench.
4. Remove the old spark plugs with a spark plug socket.
5. Inspect the new spark plugs for correct gap and install them in the correct order.
6. Reinstall ignition coils and reconnect their electrical connectors.
7. Torque the spark plugs to the manufacturer's specification (typically around 13 lb-ft).

3. Inspect and Replace Ignition Coils (if necessary)

1. If misfire persists, test each ignition coil with a multimeter to ensure they are functioning correctly.
2. Replace any faulty ignition coils with new ones, ensuring they are compatible with the specific engine model.
3. Reinstall the ignition coils and reconnect the electrical connectors.

4. Check Fuel System

1. Connect the fuel pressure gauge to the fuel rail.
2. Turn the ignition on without starting the engine and check the fuel pressure reading.
3. If the pressure is low, inspect the fuel pump and fuel filter for blockages or failures. Replace as necessary.

5. Inspect for Vacuum Leaks

1. Visually inspect intake hoses, gaskets, and the manifold for cracks or leaks.
2. If leaks are suspected, use a smoke machine to identify leaks or apply carburetor cleaner while the engine is running to see if RPM changes occur.
3. Replace any damaged hoses or gaskets found during inspection.

6. Conduct a Compression Test

1. Remove spark plugs and insert a compression gauge into each cylinder.
2. Crank the engine and record the compression readings for each cylinder.
3. If compression is low, further diagnostics may be needed to check for internal engine issues.