What does the P0020 fault code mean?
The P0020 fault code, applicable to all car manufacturers, means “A Camshaft Position Actuator Circuit/Open (Bank 2)“.
Background Information: The camshaft controls the opening and closing of the valves. In a variable valve timing system, the electronic camshaft adjusting valve (or oil control valve, OCV) adjusts the camshaft angle by changing the oil pressure to the camshaft adjuster (mechanical) according to instructions from the engine control module (ECM), ensuring the valves open and close at the optimal time. Possible causes for P0020 include the A intake/left/front camshaft adjusting valve (oil control valve), its circuitry, connectors, excessively dirty oil, or the ECU. “A” camshaft must refer to the “intake,” “left,” or “front” camshaft. Determine left/right and front/rear by looking forward from the driver’s position. The first group refers to the group including cylinder 1, and the second group is the group opposite the first.
Symptoms of P0020 Error Code
- Unstable engine idle
- Reduced engine power
- Increased fuel consumption
- Difficulty starting the engine
- Check engine light illuminated
Main Causes of P0020 Error Code
- Damaged or worn wiring to the VVT solenoid
- Defective solenoid itself
- Engine control module (ECU) malfunction or error
- Oil sump contamination or insufficient oil pressure
- Mechanical damage in the valve timing mechanism
P0020 Error Code in Different Vehicles
Toyota P0020: In Toyota vehicles equipped with the VVT-i system, the P0020 error is usually caused by clogged oil passages or a faulty phase control valve. Regular oil changes are especially important.
Ford P0020: In Ford models equipped with Duratec engines, this problem may manifest as a faulty phase control solenoid. There may also be a problem with the control unit.
BMW P0020: In BMW vehicles equipped with VANOS, the error indicates a solenoid malfunction or abnormal oil pressure. Changing the oil and filter usually helps.
Chevrolet P0020: On Chevrolet Ecotec engines, the P0020 error may be due to worn wiring or contamination of the VVT system. Checking the valves is necessary.
Nissan P0020: In Nissan vehicles equipped with the CVTC system, the error may be due to low oil pressure or a faulty solenoid. A comprehensive diagnosis is required.
How to Diagnose P0020 Error Code?
Step 1: Read the error code using an OBD2 diagnostic scanner.
Step 2: Visually inspect the wiring and connectors leading to the VVT solenoid (solenoid bank 2).
Step 3: Measure the valve resistance with a multimeter. Compare the value to the manufacturer’s specifications.
Step 4: Check the oil level and condition. Contaminated oil can interfere with the VVT system.
Step 5: Test the solenoid using diagnostic equipment, if this function is supported.
| Possible Causes | How to Check？ |
|---|---|
| Damaged wiring | Visual inspection, multimeter check |
| Faulty VVT solenoid valve | Remove and check winding resistance |
| ECU malfunction | Diagnose using an OBD2 scanner |
| Low oil level or dirty oil | Check engine oil level and condition |
| Contaminated VVT valve or filter | Remove the valve and visually inspect for contaminants |
Tools needed: OBD2 diagnostic scanner, multimeter, a set of wrenches and screwdrivers, connector puller (if needed)
How to fix P0020 error code? (Solutions to the problem)
Simple troubleshooting methods
- Reset the error code and recheck (if the error was accidental)
- Clean or replace the engine oil
- Visual inspection and repair of damaged wiring
In-depth diagnostic and repair solutions
- VVT solenoid valve replacement
- Flushing of the oil system and VVT channels
- Flashing or replacement of the engine control unit (ECU)
- Check the timing chain for wear or incorrect phase setting
Troubleshooting by symptoms
| Symptom | Possible solution |
|---|---|
| Unstable engine operation | VVT valve inspection and replacement, system cleaning |
| Increased fuel consumption | VVT system check, oil change |
| Error does not reset | Check ECU, wiring integrity and connectors |
P0020 Error Frequently Asked Questions
Can you drive with error code P0020?
It is not recommended, as improper valve timing can lead to reduced engine power and increased wear on components.
Can error P0020 be caused by dirty oil?
Yes, contaminated engine oil can clog the VVT valve or oil passages, leading to this error.
How can I quickly reset the P0020 error code?
You can disconnect the battery for 10-15 minutes, or reset the error with an OBD2 scanner. However, the error will reappear if the cause is not addressed.
Do I need to immediately replace the VVT valve with error P0020?
Not necessarily. First, it is recommended to perform a diagnosis: check the wiring, oil condition, and the valve itself. Sometimes cleaning or changing the oil is enough.
Is the P0020 error harmful to the engine?
Yes, if you ignore this problem, serious valve timing malfunctions can occur, which can damage the engine.
Related OBD2 Errors:
P0010 – A Camshaft Position Actuator Circuit/Open (Bank 1)
P0011 – A Camshaft Position – Timing Over-Advanced or System Performance (Bank 1)
P0021 – A Camshaft Position – Timing Over-Advanced or System Performance (Bank 2)
Important! If the P0020 error is not resolved promptly, it may lead to improper valve timing and severe engine wear. Regularly change the engine oil and filter to prevent clogging of the VVT system. Do not delay diagnosis and troubleshooting if a problem occurs.