how to repair a P0301 code in my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather necessary tools: OBD-II scanner, spark plug socket, torque wrench, compression tester, multimeter, vacuum gauge, and basic hand tools.
• Ensure the vehicle is parked on a level surface and the engine is off. Disconnect the battery before proceeding.

2. Inspect and Replace Spark Plug

• Remove the engine cover if necessary to access the spark plugs.
• Using the spark plug socket, carefully remove the spark plug from cylinder 1.
• Inspect the spark plug for signs of wear, carbon buildup, or damage. Replace if necessary.
• Install the new spark plug, ensuring it is torqued to the manufacturer's specifications (typically around 13 ft-lbs).
• Reconnect any wiring or components removed during the process.

3. Inspect and Replace Ignition Coil

• Locate the ignition coil on cylinder 1 and disconnect the electrical connector.
• Remove the mounting bolts securing the ignition coil using appropriate socket.
• Carefully pull the ignition coil out of the spark plug tube.
• Install the new ignition coil, securing it with bolts and reconnecting the electrical connector.

4. Fuel Injector Testing and Replacement

• Disconnect the fuel injector connector for cylinder 1.
• Use a multimeter to check the resistance of the fuel injector. Compare readings to specifications (typically around 12-16 ohms).
• If the injector is faulty, remove it by unscrewing the retaining clips or bolts and carefully pull it out from the fuel rail.
• Install the new fuel injector, ensuring proper alignment and sealing, and reconnect the electrical connector.

5. Compression Test

• Insert the compression tester into the spark plug hole of cylinder 1.
• Crank the engine several times and record the maximum compression reading.
• Compare the reading to manufacturer specifications (typically around 150-200 psi). If low, further investigation into internal engine issues may be needed.