what does code P0021 mean for my Toyota Corolla E170 (2013-2019)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety during repair.
• Raise the vehicle and secure it on jack stands if necessary.

2. Inspect and Replace the VVT Oil Control Valve

• Tools Required: Socket set, ratchet, torque wrench, screwdriver, replacement VVT oil control valve.
• Remove the engine cover if applicable.
• Disconnect the electrical connector from the VVT oil control valve.
• Remove the bolts securing the VVT oil control valve using a socket set.
• Carefully remove the valve from the engine.
• Compare the old valve with the new one to ensure correct fitment.
• Install the new VVT oil control valve and torque the bolts to the manufacturer’s specifications (typically around 8-10 ft-lbs).
• Reconnect the electrical connector.

3. Change Engine Oil and Filter

• Tools Required: Oil filter wrench, drain pan, funnel, new oil filter, and appropriate engine oil (usually 0W-20 for the Corolla).
• Position the drain pan under the oil pan and remove the oil drain plug.
• Allow the oil to fully drain, then replace the drain plug and torque to specification.
• Remove the old oil filter using an oil filter wrench.
• Install the new oil filter by hand, ensuring a proper seal.
• Fill the engine with new oil using a funnel, then check the level with the dipstick.

4. Reset the Check Engine Light

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0021 code from the ECM.
• Start the engine and allow it to reach operating temperature.