how to diagnose P0302 misfire code in Toyota Camry Seventh Generation (2012-2017)

Solution

1. Preparation

• Ensure the vehicle is parked on a level surface, and the engine is turned off and cool.
• Gather tools and parts required for the repair.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, gap gauge
• Remove the engine cover if applicable.
• Disconnect the ignition coil wiring harness and remove the ignition coil.
• Remove the spark plug using a spark plug socket.
• Inspect the spark plug for wear; if damaged, replace it with a new one.
• Check the spark plug gap against 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).
• Reinstall the ignition coil and reconnect the wiring harness.

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set
• If the spark plug is in good condition, remove the ignition coil from cylinder 2.
• Swap the ignition coil with another cylinder (e.g., cylinder 1) and clear the codes.
• Test drive the vehicle and check if the P0302 code returns to cylinder 2. If it does, replace the ignition coil.

4. Check Fuel Injector

• Tools Required: Multimeter, fuel injector cleaner
• Disconnect the fuel injector connector for cylinder 2.
• Measure the resistance of the fuel injector using a multimeter; compare to specifications (typically 12-16 ohms).
• If the resistance is out of range, replace the fuel injector.
• If within range, use a fuel injector cleaner to clean the injector and ensure proper operation.

5. Perform Compression Test

• Tools Required: Compression gauge
• Remove the spark plug from cylinder 2.
• Screw in the compression gauge and crank the engine a few times.
• Record the compression reading and compare it to manufacturer specifications (usually around 180-220 psi).
• If the compression is low, further investigation into valve or piston issues may be necessary.