P0016: Crankshaft Position and Camshaft Position Correlation (Bank 1 Sensor A)

What P0016 means

The crankshaft and camshafts are tied together by a timing chain or belt, so their positions should always match. The computer reads both with sensors and compares them. P0016 sets when the bank 1 intake cam (sensor A) is out of step with the crank by more than it allows.

The most serious cause is mechanical: a stretched timing chain, a worn tensioner or guide, or a belt that has skipped a tooth. Less serious causes include a failing cam or crank sensor, a damaged reluctor ring the sensor reads, or a variable valve timing part that is stuck.

If the timing is badly off on an interference engine, valves can hit pistons. That is why this code deserves prompt attention even when the engine still runs.

Common causes (cheapest likely first)

1. Low or degraded engine oil. Oil feeds the chain tensioner and the cam phaser. Check level and condition first.
2. Faulty camshaft or crankshaft position sensor, or wiring. A weak or noisy signal can mimic a timing problem. A scope or scan data helps.
3. Stuck variable valve timing part. A sticking oil control valve or phaser can hold the cam out of position.
4. Stretched timing chain, worn tensioner, or worn guides. Often heard as a rattle at cold start. A big job but common at high mileage on some engines.
5. Timing belt skipped a tooth or was installed wrong. Check recent timing belt work first.
6. Reluctor ring moved or damaged. Some manufacturer guidance lists this as a cause when other checks pass.

Symptoms

• Check engine light
• Rattle from the timing cover, especially at cold start
• Long crank or no start
• Rough running or low power
• Stalling
• Other cam timing codes such as P0017 or P0011

DIY difficulty: Hard

Checking oil and testing sensors are reasonable DIY steps. Confirming chain stretch usually takes scan data and service information, and timing chain replacement is a long, precise job best left to a shop.

Tools: OBD-II scanner with cam and crank data, Multimeter, Correct engine oil and filter, Service manual, Mechanic's stethoscope

Estimated repair cost

This is an estimate, built from typical parts price ranges plus labor hours times an assumed shop rate of $110 to $190 per hour. Actual prices vary by vehicle, region, and shop. Diagnosis fees are often extra.

Watch a repair video

Search YouTube for “P0016 fix” videos. Pick a recent video that matches your engine, and confirm the diagnosis before buying parts.

P0016 by make

Brand specific notes: Chevrolet, GMC, Buick, Volkswagen. Other makes: the code works the same way; see all makes.

Related codes

• P0011"A" Camshaft Position Timing Over Advanced or System Performance (Bank 1)
• P0300Random or Multiple Cylinder Misfire Detected
• P0128Coolant Thermostat (Coolant Temperature Below Regulating Temperature)

Check for recalls

Before paying for a repair, enter your VIN in the NHTSA recall lookup. Emissions parts may also be covered by a federal emissions warranty; check your warranty booklet.

FAQ