how to fix P0021 code in Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety during the repair.
• Allow the engine to cool completely.

2. Change Engine Oil

• Sub-steps:
  1. Raise the vehicle using a jack and secure it with jack stands.
  2. Remove the oil drain plug and allow old oil to completely drain into a pan.
  3. Replace the oil filter with a new one.
  4. Reinstall the drain plug; torque to manufacturer specifications (usually around 20 lb-ft).
  5. Refill the engine with the correct type and amount of oil (typically 0W-20 for Honda).

3. Inspect and Replace VVT Solenoid

• Sub-steps:
  1. Locate the VVT solenoid on the engine (usually near the camshaft).
  2. Disconnect the electrical connector from the solenoid.
  3. Remove the bolts securing the solenoid; typically requires a socket set.
  4. Inspect the solenoid for any signs of wear or blockage. If necessary, replace with a new unit.
  5. Reinstall the solenoid and reconnect the electrical connector.

4. Check and Replace Oil Control Valve (OCV)

• Sub-steps:
  1. Locate the OCV, usually near the VVT solenoid.
  2. Disconnect the wiring harness from the OCV.
  3. Remove the OCV using the appropriate socket size.
  4. Inspect for any obstructions or damage; replace if faulty.
  5. Reinstall the OCV and reconnect the wiring harness.

5. Clear Codes and Test

• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0021 code.
  3. Take the vehicle for a test drive to check if the code reappears.