What P0023 means
The engine control module drives the oil control valve (a pulse-width modulated solenoid) of the variable valve timing on the exhaust camshaft on bank 2.
How the engine computer detects it
It checks the electrical state of this output and sets the code when the circuit is open, or when the measured state does not match the command, for example because of a short. Camshaft adjustment is then disabled and the phaser stays in its locked rest position: the engine keeps running, but with less torque and higher consumption. Bank 2 exists only on V and boxer engines; it is the cylinder bank without cylinder 1.
Written from public technical sources and not yet checked by a mechanic. How we write these pages
Symptoms
- Check engine light on
- Less pulling power at low and medium engine speed
- Rough idle in some engines
- Slightly higher fuel consumption
Common causes
- Solenoid coil of the oil control valve open or shorted Most likely
- Connector corroded, loose or soaked with engine oil wicking through the valve Most likely
- Wiring harness chafed through or broken Possible
- Supply voltage missing, e.g. blown fuse Possible
- Output driver in the engine control module faulty Less likely
How to diagnose P0023
- Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
- Inspect the parts involved: oil control valve exhaust bank2, oil control valve wiring, engine control module.
- Work through the causes above from most to least likely, cheapest checks first.
- Clear the code and drive a full drive cycle to confirm the repair held.
Reading the code
- P
- Powertrain
- 0
- Generic (SAE) code
- 0
- Fuel and air metering, auxiliary emission controls
- 23
- Specific fault
Questions drivers ask
Can I drive with code P0023?
Drive gently and only as far as you need to. The engine computer may limit power to protect the engine, so avoid highways and heavy traffic until it's fixed. If the check engine light starts flashing, pull over.
Will my car pass an emissions inspection with P0023?
Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.
Will P0023 clear by itself?
The light can go off after several drive cycles without the fault, but the code returns if the cause is still there. After a repair, the readiness monitors need a full drive cycle before an inspection.
Can I fix P0023 myself?
Often yes, with an OBD-II scanner and basic tools. Difficulty: medium. Start with the cheapest checks before replacing expensive parts.
This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.