how to fix P0021 code in Honda Accord 8th Generation (2008-2012)

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, multimeter, oil filter wrench, oil catch pan
• Ensure the vehicle is parked on a level surface and the engine is cool. Disconnect the battery to prevent electrical shock.

2. Change Engine Oil and Filter

• Sub-steps:
  1. Remove the oil drain plug using a socket set and allow the old oil to drain into the oil catch pan.
  2. Replace the oil filter using the oil filter wrench.
  3. Reinstall the oil drain plug and torque to the manufacturer’s specifications (typically around 30 lb-ft).
  4. Fill the engine with new oil that meets Honda’s specifications (usually 5W-20).

3. Replace VVT Solenoid

• Sub-steps:
  1. Locate the VVT solenoid on the engine. Disconnect the electrical connector.
  2. Remove the mounting bolts using a socket set.
  3. Carefully take out the old solenoid and replace it with a new one.
  4. Torque the mounting bolts to the manufacturer’s specifications (typically around 8 lb-ft).
  5. Reconnect the electrical connector.

4. Inspect and Replace Timing Chain/Belt (if necessary)

• Sub-steps:
  1. Remove any components obstructing access to the timing chain/belt (e.g., engine covers or brackets).
  2. Align the timing marks according to the manufacturer’s specifications.
  3. If the timing chain/belt is worn or misaligned, replace it following the service manual instructions.
  4. Reassemble any components removed for access.

5. Clear Code and Test

• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to clear the P0021 code from the computer.
  3. Start the engine and let it idle for a few minutes.
  4. Take the vehicle for a test drive to ensure the check engine light does not reappear.