Camshaft position · Engine code
P0016: Crankshaft Position – Camshaft Position Correlation (Bank 1 Sensor A)
The crankshaft and camshaft are supposed to stay locked in a precise relationship. The computer compared their sensor signals and found they're out of step.
What this code means
The crankshaft turns the camshaft through a timing chain or belt. The engine computer watches both shafts with their own sensors and expects a fixed relationship between them (adjusted only by the variable valve timing system).
P0016 means that relationship is off on bank 1, cam sensor A. P0017 is the same check against sensor B on bank 1, and P0018 and P0019 are bank 2.
The most common real-world cause on higher-mileage engines is a stretched timing chain, which lets the camshaft lag behind the crank. But a failing sensor, a stuck VVT phaser, or the wrong oil can produce the same code, so it's worth diagnosing before committing to a big job.
Symptoms you may notice
- Rattle from the front of the engine at cold start, lasting a few seconds
- Rough running, hesitation or reduced power
- Hard starting
- Check engine light, often with other timing or VVT codes
Common causes, most likely first
- Stretched timing chain or worn guides/tensionerThe most common cause, especially past 100,000 miles or with infrequent oil changes.
- Timing belt that jumped a toothOn belt-driven engines, usually after a belt has aged or a tensioner has failed.
- Stuck variable valve timing phaser or solenoidThe cam is held out of its normal position.
- Low or wrong engine oilAffects the tensioner and VVT system on many engines.
- Failing cam or crank sensorA sensor reading incorrectly can mimic a real timing problem.
- Recent timing work done incorrectlyIf the code appeared right after a repair, check this first.
What to check first
- Check oil level and condition. Correct it if needed.
- Listen for a rattle at cold start; that's a strong hint toward chain wear.
- Note any companion codes: P0011–P0014 (VVT) or P0340–P0345 (sensors) change where to look first.
- A shop can read cam/crank correlation values with a scan tool; many manufacturers publish a limit that indicates chain stretch.
- Confirming actual mechanical timing (timing marks or a scope comparison) before ordering a chain kit avoids replacing the wrong parts.
Typical repairs and rough cost
| Repair | Typical cost | Notes |
|---|---|---|
| Cam or crank sensor | $100–$300 | If testing points to a sensor. |
| VVT solenoid | $150–$450 | |
| Timing belt kit | $500–$1,200 | Often includes the water pump. |
| Timing chain kit (chain, guides, tensioner) | $1,000–$2,500+ | Labor-heavy; varies widely by engine. |
Rough US shop prices for parts and labor. Your cost depends on the vehicle, the parts brand and local labor rates.
Official code definitions
| Code | Applies to | Definition |
|---|---|---|
| P0016 | Generic | Crankshaft Position - Camshaft Position Correlation Bank 1 Sensor A |
| P0017 | Generic | Crankshaft Position - Camshaft Position Correlation Bank 1 Sensor B |
| P0018 | Generic | Crankshaft Position - Camshaft Position Correlation Bank 2 Sensor A |
| P0019 | Generic | Crankshaft Position - Camshaft Position Correlation Bank 2 Sensor B |
“Generic” codes mean the same thing on every make. Manufacturer entries are that brand’s own description. Look up any other code in the code library.
Common questions
Does P0016 always mean a timing chain?
No. It's the most common cause on high-mileage engines, but a bad sensor, a stuck VVT phaser or low oil can cause it too. Get it diagnosed before paying for a chain job.
How long can I drive with P0016?
It's not one to sit on. If the chain or belt is stretching or skipping, it can fail suddenly, and on interference engines that can damage valves and pistons.
Why does my engine rattle for a few seconds on startup?
Commonly a worn timing chain tensioner or stretched chain. Oil pressure takes a moment to build and take up the slack. That noise together with P0016 is a strong sign.
Related codes
This guide explains what the code usually means and how it’s typically diagnosed. Every car is different, and a code points to a system, not always a specific part. For anything affecting brakes, steering or a car that feels unsafe, have a qualified mechanic confirm before you rely on it.