Crankshaft/Camshaft Position Correlation (Bank 1, Sensor A)
In short
P0016 means the camshaft and crankshaft are out of their expected timing relationship — the computer compares the two position sensors and they don't line up. The most common real-world causes are a stretched timing chain (and worn guides/tensioner), a stuck or failed VVT/cam phaser, or low/dirty oil starving the variable-valve-timing system. It's more serious than a simple sensor code and shouldn't be driven hard until diagnosed.
Is it safe to drive with P0016?
Limit driving until it's diagnosed. P0016 often points to timing-chain stretch or a VVT phaser problem; if a chain jumps a tooth, an interference engine can suffer serious valve/piston damage. The car may run rough or enter limp mode. Check oil level immediately and avoid hard acceleration until you know whether it's a sensor, oil, or mechanical cause.
Symptoms
- Check engine light on
- Rattle from the timing cover, especially on cold start (worn chain/tensioner)
- Hard starting, rough idle, or hesitation
- Reduced power; possible limp mode
- Sometimes accompanies cam/crank sensor codes
Common causes (most → least likely)
How to diagnose it (before buying parts)
- 1 Check engine oil level and condition FIRST. Low or sludgy oil starves the VVT phasers and oil control valves and is a common, cheap cause of correlation codes.
- 2 Listen for a timing-chain rattle on cold start — a brief rattle that fades as oil pressure builds points to a stretched chain and worn tensioner.
- 3 Remove and inspect the oil control valve (VVT solenoid) and clean its screen; a clogged screen mimics phaser failure.
- 4 Use a scan tool to command the camshaft actuator and watch whether cam timing responds; no response points to a stuck phaser or OCV.
- 5 Verify the cam and crank sensors and their reluctor rings are good and the connectors are clean.
- 6 If oil, OCV, and sensors are good, measure timing-chain stretch / cam timing against spec — chain replacement is the likely fix.
Repair options & cost
By manufacturer
Timing-chain stretch on 2.0/2.4 Ecotec and some V6s is a well-known P0016 cause, often tied to skipped oil changes. Check oil and the OCV first, but be prepared for a chain job.
VVT phaser and timing-chain wear on some EcoBoost and modular engines; rattle on cold start is the classic sign. Use OEM phasers/chains.
Oil control valve and timing-chain/phaser issues appear on several GDI engines; verify oil condition and OCV operation first.
VANOS (VVT) solenoids and timing-chain issues are known correlation-code sources; clean/replace the VANOS solenoids before assuming chain wear.
Frequently asked questions
Is P0016 serious?
It can be. It often points to timing-chain stretch or a VVT phaser problem rather than a simple sensor. If a worn chain skips a tooth on an interference engine, it can cause major valve and piston damage — so don't drive it hard until you know the cause.
Can low oil cause P0016?
Yes. The variable-valve-timing phasers are oil-pressure-operated, so low or dirty oil — or a clogged oil control valve screen — can throw cam/crank correlation codes. Always check oil level and condition first; it's the cheapest possible fix.
Can I drive with P0016?
Only minimally and gently, until diagnosed. The engine may run rough or go into limp mode, and there's a risk of timing-chain-related mechanical damage. Check your oil and get it looked at promptly.
What's the difference between P0016 and a cam sensor code?
A cam sensor code (like P0340) means the signal itself is missing or bad. P0016 means both the cam and crank signals are present but out of their expected alignment — pointing more toward timing/VVT mechanical issues than a single failed sensor.