A Camshaft Profile Actuator C Control Performance/Stuck Off Bank 1

Where it lives

For P03EF, the part to look at first is the actuator named here. The description of P03EF puts it on bank 1.

What to check first

For P03EF, check the bank 1 reading against the other bank before buying parts, since if only one side is out of range that side is the fault.

Check these first

• P03EF: Failing ignition coil, spark plug, or spark plug wire
• P03EF: Faulty crankshaft or camshaft position sensor
• P03EF: Wiring or connector damage in the ignition circuit
• P03EF: Low compression or engine mechanical wear
• P03EF: Incorrect ignition timing or a stretched timing chain

What to do next

P03EF belongs to the ignition and misfire system. These are the general steps for P03EF, and the exact cause on your vehicle can differ.

1. P03EF: Read misfire counts and freeze frame data with an OBD-II scanner
2. P03EF: Test spark output and inspect spark plugs and coils
3. P03EF: Check crankshaft and camshaft position sensor signals while cranking
4. P03EF: Swap suspect ignition parts between cylinders to see if the fault moves
5. P03EF: Compression test if the issue persists on the same cylinder

Look up another code