P0016 fault code: crankshaft and camshaft mismatch
Plain-language definition
Crankshaft Position - Camshaft Position Correlation Bank 1 Sensor A
What does it mean?
The crankshaft turns with the movement of the pistons, while the camshaft opens and closes the valves; the two are linked by a timing belt or chain and must always turn in a set angular relationship. The engine computer compares the crank and cam sensor signals to monitor whether this relationship is as it should be.
P0016 means the position of the camshaft monitored by "Sensor A" on Bank 1 (the intake camshaft on most engines) is outside the allowed range relative to the crankshaft. On engines with variable valve timing, the engine computer deliberately advances or retards the camshaft a little; that's why problems in the camshaft adjuster, or in the circuit that operates it with oil pressure, can also cause this code. A stretched timing chain or a belt that has jumped a tooth is also among the common causes.
You may notice the check engine light coming on, the engine being hard to start, rough idling and a loss of power. When the chain is the cause, you may hear a brief rattle or ticking from the engine, especially on a cold start. On some cars there may be no obvious symptom other than the light.
How serious is it?
This is a Warning-level code, but if the cause is a stretched timing chain or a belt that has jumped, the problem can progress and seriously damage the engine. That's why it's important to find the cause early.
Severity is a guide; if the warning light is flashing or you notice symptoms while driving, have the car checked at a workshop.
Common general causes
- A fault in the variable valve timing (camshaft adjuster) solenoid valve or in the adjuster
- A stretched timing chain, or wear in the tensioner and guides
- Engine oil that's low, old or the wrong viscosity (the adjuster works on oil pressure)
- A timing belt or chain that has jumped a tooth, or incorrect timing after a timing belt or chain replacement
- A problem with the crank or cam sensor, or with the trigger wheel they read
The list shows general causes; a workshop finds the actual cause on your car with a check.
Definitions by make
Some manufacturers record the same code under their own wording:
- Fiat
- Phase offset between camshaft (phase) sensor and engine speed sensor
Related codes
How does it appear in the 2dakika report?
Crankshaft Position - Camshaft Position Correlation Bank 1 Sensor A
If the code is read as a confirmed (stored) fault, the report shows it with the "Warning" severity; in pending or past records, codes that don't request the warning light and aren't critical appear as "Info". If the engine computer stored them, the conditions when the fault was recorded (engine temperature, rpm, speed) are shown too.
Read this code with the OBD-X1, and clear it from the app after the repair.
Clearing the code doesn't fix the fault; if the problem persists, the code comes back.