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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Engine Oil

• Sub-steps:
  1. Check the engine oil level with the dipstick.
  2. If low or dirty, drain the old oil using a wrench to remove the oil drain plug.
  3. Replace with the recommended engine oil (5W-20 for Honda Accord).
  4. Replace the oil filter if necessary.
  5. Reinstall the drain plug and torque to manufacturer specifications (typically 33 lb-ft).

3. Replace VVT Solenoid

• Tools Required: Socket set, torque wrench, new VVT solenoid.
• Sub-steps:
  1. Locate the VVT solenoid on the engine.
  2. Disconnect the electrical connector from the solenoid.
  3. Remove the mounting bolts (typically 10 mm) and take off the solenoid.
  4. Install the new VVT solenoid and torque bolts to manufacturer specifications (typically 8.7 lb-ft).
  5. Reconnect the electrical connector.

4. Verify Timing Chain/Belt Alignment

• Sub-steps:
  1. Remove any necessary components (e.g., engine cover) to access the timing chain/belt.
  2. Check the alignment marks on the camshaft and crankshaft sprockets.
  3. If misaligned, reset the timing by following the manufacturer’s timing alignment procedure.

5. Reconnect Battery and Test

• Reconnect the negative battery terminal.
• Start the engine and allow it to reach operating temperature.