P0316

Powertrain
Generic (SAE)
Emissions

Severity

Diagnose soon

The misfire is brief and self-clearing, so cumulative catalyst exposure per start is small. It is still real unburned fuel reaching the converter every single cold start, and P0316 frequently precedes a full-time misfire as the underlying part degrades. If the MIL flashes during the startup period, or cylinder-specific misfire codes accompany it and persist while running, treat it as high instead.

Safe to drive: Generally safe to drive short term if the engine smooths out and the light stays steady. If the light ever flashes, stop driving and have it towed. Diagnose before it becomes a running misfire.

Standard definition

Engine Misfire Detected on Startup (First 1000 Revolutions)

In plain English

The computer detected misfires during the first 1000 crankshaft revolutions after the engine started, and then the engine ran acceptably. It is a start-only misfire code — it tells you when the problem happens, not what caused it.

P0316 is a windowed misfire report. Some manufacturers suppress normal misfire diagnostics briefly after startup because a cold, rough-running engine produces crank speed variation that would falsely trip the standard monitor. This code exists to catch misfires in that early window without confusing them with running misfires. Many applications set P0316 alongside cylinder-specific codes such as P0301 through P0308; on others the cylinder identity is only visible in Mode $06 or manufacturer misfire-count data.

How the car detected it

Immediately after start, the PCM counts crank acceleration deficits in the same way it does at running speed, but tallies them against a counter that is only open for the first 1000 revolutions. If the count exceeds the calibrated limit within that window, P0316 sets. Because the window is short, the code often stores with no drivability complaint once the window closes — roughly a minute after start depending on idle speed — and the engine may be perfectly smooth by the time you look at it.

A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.

Can I keep driving?

Safe to drive: Generally safe to drive short term if the engine smooths out and the light stays steady. If the light ever flashes, stop driving and have it towed. Diagnose before it becomes a running misfire.
Urgency: Diagnose soon
Will it pass emissions: No
If ignored: The underlying weakness usually worsens. Fouled plugs foul further, a marginal coil fails outright, and what was a start-only code becomes a continuous misfire with the catalyst damage that goes with it. If the cause is an overnight fuel leak past an injector or a failing check valve, that fuel is also washing a cylinder wall and diluting engine oil at every soak.
Check engine light: Solid
Clearing the light: A completed drive cycle is normally required before the monitor re-runs and the light can clear.

Symptoms you may notice

Check engine light on or flashing
Rough idle and uneven running
Power loss, hesitation under acceleration
Increased fuel consumption
Possible smell of unburned fuel from exhaust

Many vehicles show no symptom at all beyond the warning light. The absence of a symptom does not mean the fault is not real.

Likely causes

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	Spark plugs fouled when cold	Very common	—
2	Ignition coil weak below operating temperature	Common	—
3	Cold-start mixture too lean (fuel pressure, leaking injectors at rest)	Common	—

Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.

What to check first

In order. Each of these is cheaper or faster than what follows it, and each one can make the rest unnecessary.

Which cylinders the misfire counts land on during startup
One cylinder points at that cylinder's coil, plug, injector or compression. All cylinders points at fuel supply, cam timing, or a system-wide condition.
Whether the code sets only after a long soak or on every start
Long-soak-only strongly suggests fuel rail pressure bleeding down overnight or fuel pooling in a cylinder. Every-start suggests plugs, coils, or compression.
Spark plug condition and age
Plugs at or past their interval that foul when cold and burn clean when hot are a common and cheap-to-check cause, and reading them takes minutes.
Fuel rail pressure immediately at key-on after an overnight sit
A rail that has bled to zero means the engine gets a lean or delayed first fire. This is a leaking injector or a failed check valve, and it is invisible once the engine is running.
Any rattle for one or two seconds at start
A brief start-up rattle points at a variable valve timing phaser failing to lock, which parks the cam wrong and misfires until oil pressure builds. That is a different repair entirely.

How a shop diagnoses this

Record the misfire counters from a cold start
Tools Scan tool with live per-cylinder misfire data or Mode $06
Connect before the first start of the day, start the engine, and watch per-cylinder misfire counts as they accumulate through the full 1000-revolution window — about 45 to 90 seconds depending on idle speed. Note whether counts are spread evenly or concentrated.
Expected
Counts accumulate during the startup window and then stop
Read all the spark plugs
Tools Plug socket, extension, torque wrench
Look for fuel wash, oil fouling, carbon fouling, or excessive gap. A plug that is heavily carbon-fouled will fail to fire cold and clear up as combustion chamber temperature rises — exactly the pattern P0316 describes.
Expected
Uniform light tan deposits across all plugs; gap and torque are vehicle-specific
Test fuel rail pressure hold after shutdown
Tools Fuel pressure gauge or scan tool fuel pressure PID, service data for the pressure-relief procedure
Attach a gauge or monitor the fuel pressure PID, run the engine, shut it off, and watch pressure over the next thirty minutes and again after an overnight soak. Pressure should hold well above zero. The system stays pressurized after shutdown: relieve pressure by the service procedure before opening any line, keep ignition sources clear, and catch any spillage. On a direct-injected engine do not open the high-pressure side — it operates at pressures that can inject fuel through skin — read it with the scan tool PID and test the low-side circuit separately.
Expected
Pressure decays slowly. Rapid bleed-down to zero indicates a leaking injector, a failed check valve, or a leaking regulator. Hold-time specs are vehicle-specific.
Swap the coil from a suspect cylinder to another and repeat a cold start
Tools Basic hand tools, scan tool
Only meaningful once you know which cylinder is counting. A coil with a weak secondary can fire fine warm and fail under the higher voltage demand of a cold, rich cylinder.
Expected
Misfire counts move to the cylinder the coil moved to if the coil is the fault
Check cam-to-crank correlation and VVT phaser behaviour at start
Tools Scan tool with cam position PIDs, oil pressure gauge if warranted
If the engine rattles briefly at start or the code appears with cam position codes, monitor commanded versus actual cam position during the first seconds. A phaser that will not hold its park position gives wrong valve timing until oil pressure builds.
Expected
Actual cam position matching commanded within a few degrees shortly after start; the tolerance is vehicle-specific
Inspect intake valves for carbon on a direct-injected engine
Tools Borescope
Direct injection puts no fuel across the intake valve, so carbon accumulates there and disrupts airflow and mixture at low speed and cold temperature. Borescope through the intake port or remove the intake manifold.
Expected
Clean valve tulips. Heavy black crust restricting the port is the finding.
Run a cold compression test if plugs, coils, fuel and timing all check out
Tools Compression gauge
A valve or ring that does not seal cold but seals once the engine expands with heat produces exactly this code. Test the engine cold, before it has run.
Expected
All cylinders within a tight band; an outlier that improves when the test is repeated warm confirms a cold sealing problem

Possible repairs and what they cost

Repair	Only after you confirm	Typical cost	Who
Replace the spark plugs	Plugs show fouling, wear, or excessive gap, and cold-start misfire counts stop after replacement	$90–$450	DIY
Replace the coil serving the counting cylinder	Cold-start misfire follows the coil when it is swapped to another cylinder	$70–$320	DIY
Replace a fuel injector that leaks down at rest	Rail pressure bleeds to zero after shutdown and the affected cylinder's plug shows fuel wash. On a direct-injected engine, confirm with the manufacturer's injector leak-down or balance test rather than by swapping injectors between cylinders.	$180–$700	DIY
Replace the fuel pump check valve or pressure regulator assembly	Rail pressure bleeds down with the injectors ruled out by clamping or substitution testing	$300–$1,100	DIY
Replace a variable valve timing phaser or its control solenoid	Start-up rattle present and actual cam position deviates from commanded during the first seconds after start	$400–$2,200	Hard
Walnut-blast or manually clean carboned intake valves on a direct-injected engine	Borescope shows heavy intake valve deposits and the misfire is cold and low-load	$400–$1,200	Hard
Internal engine repair for a cylinder that does not seal cold	Cold compression shows one cylinder well below the others and it improves when tested warm	$1,200–$5,000	Shop

US independent-shop ranges, parts plus labour. Cost is driven almost entirely by which cause is confirmed, so diagnosis matters more here than on most codes. Expect one to two hours of diagnostic labour, and understand that a technician may need the car overnight to test it from a genuine cold start.

Common mistakes with this code

Reading P0316 as a distinct fault and searching for a part called out by that number. It is a timing window, not a component.
Test-driving the car warm, finding no misfire, and calling it intermittent. The detection window is the first 1000 revolutions after any start — most often it reproduces after a full cold soak, but it can also set on a hot restart, so test both.
Replacing coils without first confirming which cylinder the counts land on.
Ignoring an accompanying start-up rattle, then replacing plugs and coils on an engine whose real fault is a cam phaser.
Skipping the overnight fuel pressure hold test because rail pressure reads normal with the engine running.
Clearing the code and assuming it is fixed because it takes several cold starts to reappear.

Components involved

Sources

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

Found something wrong? Tell us — we publish corrections.

Which cylinders the misfire counts land on during startup

Whether the code sets only after a long soak or on every start

Spark plug condition and age

Fuel rail pressure immediately at key-on after an overnight sit

Any rattle for one or two seconds at start

Record the misfire counters from a cold start

Read all the spark plugs

Test fuel rail pressure hold after shutdown

Swap the coil from a suspect cylinder to another and repeat a cold start

Check cam-to-crank correlation and VVT phaser behaviour at start

Inspect intake valves for carbon on a direct-injected engine

Run a cold compression test if plugs, coils, fuel and timing all check out