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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.

2. Replace Spark Plugs

1. Remove the ignition coil covers (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. Inspect the spark plug holes for debris and clean if necessary.
5. Install new spark plugs, ensuring they are gapped correctly (typically 0.043 inches for Toyota).
6. Torque the spark plugs to manufacturer specifications (usually around 13 lb-ft).

3. Inspect and Replace Ignition Coils (if necessary)

1. Remove the ignition coils from the spark plugs.
2. Test each ignition coil with a multimeter for resistance (typically 0.4 - 0.6 ohms) and replace any that are out of spec.
3. Install new ignition coils, ensuring a secure fit and proper connection.

4. Check and Adjust Fuel System

1. Connect a fuel pressure gauge to the fuel rail.
2. Turn the ignition to the "ON" position without starting the engine to check fuel pressure (should be around 50-60 psi).
3. If pressure is low, inspect the fuel filter and fuel pump for proper operation and replace as necessary.

5. Inspect Air Intake and Vacuum System

1. Check the air intake hose for cracks or leaks; replace if necessary.
2. Inspect the throttle body for carbon buildup and clean it if needed.
3. Use a vacuum gauge to check for leaks in the vacuum system and repair any found.