how to fix P0021 code in Toyota Corolla E140 (2006-2013)

Solution

1. Preparation

• Gather tools and parts. Ensure the vehicle is parked on a level surface.
• Disconnect the battery to avoid any electrical issues during repairs.

2. Inspect and Replace VVT Oil Control Valve

• Tools Required: Socket set, wrench set, screwdriver, new VVT oil control valve.
• Remove the engine cover by unscrewing any retaining bolts.
• Locate the VVT oil control valve; disconnect the electrical connector and remove the mounting bolts.
• Install the new VVT oil control valve by reversing the removal steps. Ensure it is secured tightly and the connector is reattached.

3. Change Engine Oil and Filter

• Tools Required: Oil filter wrench, oil drain pan, socket set.
• Raise the vehicle using a jack and secure it with jack stands.
• Drain the old engine oil by removing the oil drain plug and allowing it to completely drain into the pan.
• Replace the oil filter using an oil filter wrench.
• Reinstall the drain plug and refill the engine with new oil that meets Toyota specifications.

4. Check and Adjust Camshaft Timing

• Tools Required: Timing light, socket set, torque wrench.
• Remove any components obstructing access to the timing cover.
• Align the timing marks on the crankshaft and camshaft according to the manufacturer specifications.
• If misaligned, adjust the timing chain/belt accordingly and tighten all bolts to the specified torque values.

5. Reassemble and Test

• Reinstall any components removed during the procedure (engine cover, accessories).
• Reconnect the battery.
• Start the engine and check for any leaks or abnormal noises.