what does code P0301 mean for my Toyota Corolla E210 (2019-2024)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

Tools Required:

• OBD-II scanner
• Socket set
• Torque wrench
• Compression tester
• Multimeter

2. Inspect and Replace Spark Plug

• Sub-step 1: Remove the ignition coil on cylinder 1 by unscrewing the retaining bolts and disconnecting the electrical connector.
• Sub-step 2: Remove the spark plug using a spark plug socket.
• Sub-step 3: Inspect the spark plug for wear or damage. Replace it if it appears fouled or worn (gap specification: 0.044 inches).

3. Check and Replace Ignition Coil

• Sub-step 1: Test the ignition coil with a multimeter to ensure it has the correct resistance.
• Sub-step 2: If faulty, replace the ignition coil with a new unit. Ensure it is seated properly on the spark plug.

4. Inspect Fuel Injector

• Sub-step 1: Remove the fuel injector connector from the injector for cylinder 1.
• Sub-step 2: Test the injector with a multimeter to confirm it is receiving voltage.
• Sub-step 3: If the injector is faulty, replace it with a new one, ensuring it is properly seated and connected.

5. Check for Vacuum Leaks

• Sub-step 1: Visually inspect hoses and gaskets around the intake manifold for cracks or disconnections.
• Sub-step 2: Use a smoke machine or propane torch to identify any leaks while monitoring engine idle behavior.

6. Verify Compression

• Sub-step 1: Attach the compression tester to the spark plug hole of cylinder 1.
• Sub-step 2: Crank the engine to measure the pressure. It should meet manufacturer specifications (typically around 180 psi).

7. Reassemble and Test

• Sub-step 1: Reinstall any components that were removed during inspections.
• Sub-step 2: Reconnect the negative battery terminal.
• Sub-step 3: Start the engine and check for the check engine light. Ensure the vehicle runs smoothly.