how to fix P0300 random misfire code in Toyota Tacoma N300 (2016-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical issues.

2. Replace Spark Plugs

• Sub-steps:
  1. Remove the engine cover (if applicable) using a socket set.
  2. Disconnect the ignition coils from the spark plugs.
  3. Use a spark plug socket to remove the old spark plugs.
  4. Apply anti-seize compound to the threads of the new spark plugs.
  5. Install the new spark plugs to the manufacturer’s specified torque (typically around 13 lb-ft).
  6. Reconnect the ignition coils.

3. Inspect and Replace Ignition Coils

• Sub-steps:
  1. Using a multimeter, test each ignition coil's primary and secondary resistance.
  2. Remove any faulty ignition coils.
  3. Install new ignition coils and ensure they are secured properly.
  4. Reconnect electrical connectors to the ignition coils.

4. Check Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Turn the ignition to the ON position (without starting) to check fuel pressure; it should meet manufacturer specifications (around 50-60 psi).
  3. If pressure is low, inspect the fuel pump and filter; replace as necessary.

5. Inspect for Vacuum Leaks

• Sub-steps:
  1. Start the engine and listen for unusual hissing noises indicating a vacuum leak.
  2. Use a smoke machine to identify leaks if necessary.
  3. Replace any damaged vacuum hoses or gaskets.