how to fix P0305 misfire code on Toyota Tacoma N300 (2016-Present)

Learn how to diagnose and fix P0305 cylinder 5 misfire in Toyota Tacoma N300. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Tools Required: OBD-II scanner, torque wrench, socket set, multimeter, compression tester.
• Ensure the vehicle is parked on a level surface, and the engine is cool. Disconnect the negative battery terminal.

2. Inspect and Replace Ignition Components

• Step 1: Remove the engine cover (if applicable).
• Step 2: Disconnect the ignition coil connector for cylinder 5.
• Step 3: Remove the ignition coil using a socket set (typically 10mm).
• Step 4: Inspect the spark plug; replace if worn or fouled (gap to manufacturer's specification, usually around 0.043 inches).
• Step 5: Install a new ignition coil if the old one shows signs of damage.
• Step 6: Reconnect the ignition coil and engine cover.

3. Check and Replace Fuel Injector

• Step 1: Disconnect the fuel injector connector for cylinder 5.
• Step 2: Remove the fuel rail (check for fuel leaks and relieve pressure before removal).
• Step 3: Replace the fuel injector in cylinder 5.
• Step 4: Reinstall the fuel rail and reconnect the fuel injector.

4. Perform Compression Test

• Step 1: Remove the spark plugs from cylinder 5 and adjacent cylinders if necessary.
• Step 2: Insert the compression tester into the spark plug hole of cylinder 5.
• Step 3: Crank the engine and record the compression reading.
• Step 4: Repeat for the other cylinders to compare results. A low reading may indicate a mechanical issue.

5. Reassemble and Reset Codes

• Step 1: Reinstall the spark plugs and ignition coil.
• Step 2: Reconnect the battery terminal.
• Step 3: Use the OBD-II scanner to clear the P0305 code.
• Step 4: Start the engine to ensure proper operation.