P0014
- Powertrain
- Generic (SAE)
- Emissions
Diagnose soon
Exhaust cam timing stuck advanced degrades power, idle quality, and fuel economy and will fail emissions, but the engine continues to run. It escalates if the cause is a stretched or jumped timing chain, because that condition worsens and on an interference engine can end in valve damage. Look for a companion correlation code before deciding this is a minor repair.
- Safe to drive
- Usually drivable short term with reduced power. If the engine rattles on start-up, or a crank-to-cam correlation code is present, stop driving and have it towed rather than driven — a chain that slips further on an interference engine bends valves.
"B" Camshaft Position - Timing Over-Advanced (Bank 1)
The bank 1 exhaust camshaft is sitting further advanced than the computer commanded, or it will not return when told to. That is a detection of a timing position error, not proof that any specific part has failed.
The exhaust camshaft phaser is a hydraulic actuator fed by engine oil through an oil control valve. The module compares the actual cam phase, derived from the camshaft position sensor relative to the crankshaft signal, against its commanded target. P0014 sets when actual phase remains advanced of the target beyond a calibrated error for a calibrated period. The usual mechanisms are an oil control valve that is not metering or sealing as commanded, a phaser that cannot hold or return to its commanded position, or a timing chain that is no longer in its correct relationship to the crankshaft. Which of those hydraulic conditions produces an over-advanced result depends on the phaser's parked (default) position and the oil circuit for that specific engine — on some engines oil advances the exhaust phaser, on others the phaser parks advanced and oil retards it — so confirm the direction from service data rather than assuming it.
How the car detected itThe test runs only inside an enabling window that normally includes oil at operating temperature and a defined range of engine speed and load, because cold oil moves phasers slowly and would produce false failures. The module commands a phase change, allows settling time, and measures residual error. Because a mechanically mistimed chain shifts the baseline cam position, a chain that has jumped or stretched produces this code even though the phaser and solenoid are both working.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Usually drivable short term with reduced power. If the engine rattles on start-up, or a crank-to-cam correlation code is present, stop driving and have it towed rather than driven — a chain that slips further on an interference engine bends valves.
- Urgency
- Diagnose soon
- Will it pass emissions
- No
- If ignored
- Reduced power, rough idle, higher fuel consumption, and a failed emissions test. If the real cause is a worn chain, guide, or tensioner, continued driving lets the chain slip further, and a slipped chain on an interference engine can bring pistons into contact with valves. That converts a timing job into an engine rebuild.
- Check engine light
- Solid
- Clearing the light
- A completed drive cycle is normally required before the monitor re-runs and the light can clear.
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
Many vehicles show no symptom at all beyond the warning light. The absence of a symptom does not mean the fault is not real.
These are the causes this code can have. For the order to work through them in, see what to check first.
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Oil control valve stuck (advance) | Very common | — |
| 2 | Sludge in VVT oil passages | Common | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
In order. Each of these is cheaper or faster than what follows it, and each one can make the rest unnecessary.
Engine oil level, condition, and viscosity
The phaser is hydraulically driven through fine passages. Degraded, low, or wrong-viscosity oil is the cheapest realistic cause and must be eliminated before parts are bought.
Whether a crank-to-cam correlation code such as P0016, P0017, P0018, or P0019 is also stored
A correlation code shifts the diagnosis from the phaser control system to the timing chain. That is the difference between a few hundred dollars and a few thousand, and you need to know before ordering anything.
Recent timing chain, phaser, or cylinder head work
A chain installed one tooth out is a very common cause of P0014 immediately after service, and the fix is to redo the timing, not to buy more parts.
Commanded versus actual cam angle on live data at operating temperature
This shows in seconds whether the cam is stuck at an advanced position, drifts, or responds sluggishly, and it costs nothing.
Any rattle for a second or two at cold start-up
A brief start-up rattle is the classic sign of a worn chain tensioner or guide, and it redirects the whole diagnosis before you remove a single bolt.
Record freeze frame and every stored code
Tools Scan tool
Note whether the code set hot or cold, at idle or under load, and which companion codes exist. Correlation and circuit codes alongside P0014 change the diagnostic path entirely.
ExpectedA full code list in the order the codes set, with the recorded conditions at the moment of the fault
Check oil level, condition, viscosity, and service interval
Tools Basic hand tools, service data
Inspect the filler cap and dipstick for varnish and sludge. Confirm the viscosity matches what the manufacturer specifies for that engine, which is engine-specific and cannot be assumed.
ExpectedOil full, clean, correct viscosity, within service interval
Graph commanded versus actual exhaust cam angle, fully warm
Tools Scan tool with graphing
Watch both values at idle, at a steady raised rpm, and through throttle transitions. A cam that sits advanced and will not return when the command drops to zero is the exact condition this code names. A cam that tracks correctly points at an intermittent or a chain baseline issue.
ExpectedActual cam angle returns to and holds the commanded position within a few degrees
Command the oil control valve through its range and observe
Tools Scan tool with bidirectional control
Sweep the solenoid duty cycle with bidirectional control. If the cam stays advanced regardless of command, the fault is in the valve, the phaser, or the oil path between them — check service data for which way oil moves this phaser before deciding whether you are looking for oil that is not arriving or oil that is not being cut off. If the cam responds fully, look elsewhere.
ExpectedCam position tracks the commanded sweep in both directions
Remove and inspect the oil control valve
Tools Hand tools, fused jumper leads, clean solvent
Check the inlet screen for sludge and debris. Confirm the spool moves freely and seats fully under spring force. Energize it off the vehicle to confirm full travel and full return in both directions. A spool that will not seat or will not travel is a finding either way; which one matters depends on the engine's oil circuit.
ExpectedClean screen, free spool, full travel and full return
Measure hot engine oil pressure with a mechanical gauge
Tools Mechanical oil pressure gauge and adapter
Do not trust the dash light. Measure at idle and at raised rpm with the oil at operating temperature. Port location and specification vary by engine and come from service data. Adequate pressure is a prerequisite for blaming the phaser.
ExpectedMeasured pressure meeting the engine's specified figure hot at both idle and raised rpm
Verify mechanical timing directly if the phaser and valve test good
Tools Hand tools, service data, timing tools as specified
Bring the engine to the manufacturer's timing reference position and compare the cam and crank marks, or measure tensioner extension through the access provision if the engine has one. Marks, procedure, and access all vary by engine and must come from service data. A chain off by one tooth looks exactly like a phaser fault on a scan tool.
ExpectedCam and crank marks aligned at the manufacturer's reference position, with tensioner extension or chain slack inside the service-data limit
Clear codes and confirm over a full drive cycle
Tools Scan tool with data logging
Confirm the cam now returns to commanded position at idle and under load, through a full warm-up, and that no codes return once the monitor completes.
ExpectedCam tracks command across the range, no codes return
| Repair | Only after you confirm | Typical cost | Who |
|---|---|---|---|
| Oil and filter change with the correct specified viscosity | Oil found low, sludged, overdue, or the wrong viscosity, with correct cam response restored after the change | $60–$180 | DIY |
| Replace the bank 1 exhaust oil control valve | Spool found sticking, not seating, or not travelling fully on the bench, with the cam failing to follow the commanded sweep and the electrical circuit proven good | $150–$500 | DIY |
| Engine cleaning service and correction of the cause of sludge in the oil passages | Heavy varnish or sludge found in the valve screen and internal surfaces, with adequate measured oil pressure | $200–$700 | DIY |
| Correct mechanical timing that was installed incorrectly | Direct inspection at the manufacturer's reference position showing the cam and crank marks out of alignment | $400–$1,600 | Shop |
| Replace the bank 1 exhaust camshaft phaser, normally with chain, guides, and tensioner | Verified adequate oil pressure, a proven-good solenoid, and correct mechanical timing, with the phaser still failing to hold or return commanded position | $1,000–$3,000 | Shop |
| Replace the timing chain, guides, and tensioner | Measured chain slack or tensioner extension beyond specification, or a correlation code confirming the chain has moved | $1,200–$3,500 | Shop |
The gap between the cheap end and the expensive end of this code is enormous. A solenoid job is a few hundred dollars; a chain and phaser job on a transverse V6 can approach four thousand. That is exactly why the oil, solenoid, and correlation checks come first. Ranges are US independent-shop, parts plus labor.
- Replacing the phaser without measuring oil pressure, when a phaser that cannot be supplied will not work no matter how new it is.
- Assuming the direction of the fault tells you which side of the oil circuit is at fault. Whether oil advances or retards a given exhaust phaser depends on where that phaser parks, and it varies by engine.
- Overlooking a companion correlation code that points at the timing chain, and installing phaser parts onto a stretched chain.
- Reusing a worn chain, guide, and tensioner while replacing phasers. The labor is already spent and the code will return.
- Assuming the fault is mechanical when the engine has recently had timing work done. A chain one tooth off is far more likely than a brand new part failing.
- Cleaning the oil control valve and putting it back without addressing the sludge that blocked it, which returns within months.
- Diagnosing on a cold engine. The monitor itself will not run cold, and cam response on cold oil is not representative.
- Camshaft Position Actuator
- Oil Control Valve
- Cam Phaser
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Reviewed
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