how to fix P0301 misfire code in Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, gap gauge.
• Remove the engine cover if applicable.
• Use a socket to remove the spark plug from cylinder 1.
• Inspect the spark plug for wear, carbon buildup, or damage; replace if necessary.
• Check and adjust the gap of the new spark plug according to manufacturer specifications (typically around 0.043 inches for most Toyota engines).
• Install the new spark plug and torque it to the manufacturer’s specification (usually around 13 lb-ft).

3. Check and Replace Ignition Coil

• Tools Required: Socket set, multimeter.
• Remove the ignition coil from cylinder 1 by unscrewing the retaining bolts.
• Use a multimeter to check the primary and secondary resistance of the ignition coil; compare readings with manufacturer specifications.
• If the ignition coil is faulty, replace it with a new one.
• Reinstall the ignition coil and secure it properly.

4. Fuel Injector Inspection

• Tools Required: Fuel pressure gauge, injector cleaning kit (if applicable).
• Connect a fuel pressure gauge to the fuel rail to check fuel pressure; compare it with specifications.
• If fuel pressure is low, inspect the fuel filter and pump.
• To test the injector, use a multimeter to check for resistance. If it is out of spec, replace the injector.

5. Compression Test

• Tools Required: Compression tester.
• Remove the spark plug and ignition coil for cylinder 1.
• Insert the compression tester into the spark plug hole and crank the engine to get a reading.
• Compare the compression value with manufacturer specifications; if it is low, further investigation into the engine’s internal components may be necessary.