how to fix P0301 misfire code in Toyota Camry Seventh Generation (2012-2017)

Solution

1. Preparation

• Gather tools: OBD-II scanner, socket set, torque wrench, multimeter, compression tester, and noid light.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Replace Spark Plug

• Remove the spark plug:
  • Use a spark plug socket to remove the spark plug from cylinder 1.
  • Inspect for wear, carbon buildup, or damage.
• Replace spark plug:
  • If damaged, replace with a new spark plug that meets manufacturer specifications (e.g., NGK or Denso).
  • Torque the new spark plug to the specified value (typically around 13 lb-ft).

3. Inspect and Replace Ignition Coil

• Remove ignition coil:
  • Disconnect the electrical connector and remove the bolt securing the ignition coil.
  • Pull the ignition coil out of the cylinder head.
• Test ignition coil:
  • Use a multimeter to check the resistance of the coil. If it’s outside the manufacturer’s specifications, replace it.
• Install new ignition coil:
  • Position the new ignition coil and secure it with the bolt.
  • Reconnect the electrical connector.

4. Check Fuel Injector

• Test fuel injector:
  • Connect the noid light to the electrical connector of the fuel injector for cylinder 1 to check for signal.
  • If no signal is present, diagnose the wiring or replace the injector.
• Replace fuel injector if necessary:
  • Remove the intake manifold if required to access the injector.
  • Disconnect the fuel line and electrical connector, then remove the old injector.
  • Install the new injector and ensure proper seating and connection.

5. Perform Compression Test

• Perform compression test:
  • Remove the spark plug from cylinder 1 and install the compression tester.
  • Crank the engine and record the compression reading. Compare with manufacturer specifications (typically 180-200 psi).
• Address any low compression issues:
  • If compression is low, investigate further for potential issues such as valve damage or head gasket failure.