# P0316: Engine Misfire Detected on Startup (First 1000 Revolutions) **Verdict:** Drive to a shop this week Ignition and misfire - Generic OBD-II code, applies to all gasoline cars and light trucks sold in the US since 1996. - **Typical cost:** $120-$3,500 - **Urgency:** This week - **Most likely:** Worn plugs, leaking injector or coolant leak - **DIY?:** Steps 1-2 ## Quick answer P0316 means the engine computer counted misfires during the first 1,000 crankshaft revolutions after the engine started, which at a typical cold idle is about the first minute. The engine often smooths out once it warms. Worn spark plugs, a leaking injector, carbon on the valves or coolant seeping into a cylinder are the main suspects. ## What does P0316 mean? The misfire monitor runs whenever the engine is running, but the first moments after a start get special attention. Emissions are highest then, the catalytic converter is still cold, and problems such as fuel or coolant pooling in a cylinder overnight show up most clearly. P0316 is how the computer flags misfires seen in that startup window, counted as the first 1,000 revolutions of the crankshaft rather than in seconds. The code itself does not name a cylinder. It almost always appears with a cylinder-specific code such as P0301 to P0308, or with P0300 for random misfires, and those codes tell you where to look. How many startup misfires it takes to set P0316, and whether it needs one or two trips, varies by maker. A pattern that is worse after the car sits overnight, or in cold, damp weather, is a useful clue to the cause. ## What are the symptoms of P0316? - Rough, shaky idle for the first minute after starting, then smooth - Check engine light on, usually with a cylinder misfire code - Puff of white smoke at startup if coolant is entering a cylinder - Fuel smell or long cranking if an injector is leaking - Worse symptoms after the car sits overnight or in cold weather ## What causes P0316? Ranked from most to least likely. Check them in this order: the cheap, common causes first. 1. **Worn spark plugs or weak ignition coils** (most common). A cold engine needs a strong spark because fuel does not vaporize as well and the mixture is rich. Plugs past their interval, or coils that are starting to break down, often misfire for the first minute and then recover as things warm up. Damp weather makes it worse, especially if moisture has collected in the coil boots. 2. **Leaking fuel injector or fuel pressure bleed-off** (common). An injector that drips after shutdown floods its cylinder while the car sits, so that cylinder misfires on a wet, over-rich charge at the next start. Long cranking and a fuel smell are typical. A shop checks whether fuel pressure holds after shutdown and runs an injector leak or balance test to pinpoint the cylinder. 3. **Carbon buildup on intake valves** (common). Direct-injection engines never wash their intake valves with fuel, so oily carbon can build up over tens of thousands of miles. Thick deposits soak up fuel and disturb airflow on a cold start, causing startup misfires that fade when warm. A borescope inspection through the intake shows the deposits, and walnut-shell blasting is the usual cleaning method. 4. **Coolant leaking into a cylinder** (less common). A failing head gasket, cracked cylinder head or leaking intake gasket can let coolant seep into a cylinder while the engine sits. That cylinder misfires at startup and often puffs white, sweet-smelling smoke. Falling coolant level with no visible leak is a strong sign. A cooling system pressure test and a combustion gas test confirm it. 5. **Low compression or sticking valves** (rare). A valve that sticks slightly when cold, worn piston rings or a weak valve spring can lower compression until the engine warms and parts expand. This is more likely on high-mileage engines with poor oil-change history. A cold compression test on the cylinder named by the misfire code, followed by a leak-down test, shows whether it is mechanical. ## How do you diagnose P0316? 1. Read all codes; the cylinder-specific misfire code tells you which cylinder to check first. 2. Note whether the misfire is worse after sitting overnight, in damp weather or after a short shutdown. 3. Check spark plug age and condition, and look for moisture or oil in the coil boots. 4. Check the coolant level over a few days and look for white smoke at startup. 5. Have a shop test fuel pressure hold, injector leakage and cold compression on the affected cylinder. ## How do you fix P0316, and what does it cost? | Fix | Typical cost | What it involves | | --- | --- | --- | | Replace spark plugs | $120-$600 | Four-cylinder engines at the low end, V6 and V8 engines higher. | | Replace a leaking fuel injector | $250-$1,100 | Direct-injection injectors are at the top of the range. | | Clean carbon from intake valves | $400-$900 | Usually walnut-shell blasting with the intake removed. | | Repair head gasket or coolant leak | $1,500-$3,500 | Only after a pressure or combustion gas test confirms it. | Full price breakdowns: [spark plug replacement cost](/cost/spark-plug-replacement), [fuel injector replacement cost](/cost/fuel-injector-replacement), [head gasket replacement cost](/cost/head-gasket-replacement). ## Is it safe to drive with P0316? > **Drive to a shop this week.** If the misfire clears within a minute and you are not losing coolant, you can drive normally for a short time while you book a repair. If coolant is disappearing, white smoke appears at startup or the light flashes, stop driving it, because coolant in a cylinder can cause severe engine damage. ## Will P0316 fail an emissions test? P0316 and its companion misfire codes turn on the check engine light, so the car fails an OBD-based emissions test in most states. Startup misfires also send unburned fuel into a cold catalytic converter, raising emissions. Clearing codes resets the readiness monitors, so after the repair drive for several days before going in for a retest. ## After the repair: clearing P0316 Clear the codes, then let the car sit overnight, since many startup faults only appear on a fully cold engine. Start it the next morning and watch misfire counts on a scan tool during the first minute. Repeat over several cold starts. If idle is smooth from the first seconds, the coolant level holds and no codes return, the repair worked. ## How to prevent P0316 - Replace spark plugs at the specified interval rather than waiting for a misfire. - Check coolant level monthly and investigate any loss without a visible leak. - On direct-injection engines, change oil on time with the correct spec to slow valve deposits. - Avoid repeated very short trips that never let the engine warm up fully. - Fix a fuel smell or long cranking after the car sits; both suggest a leaking injector. ## Codes often seen with P0316 - [P0300](/codes/p0300): Random/Multiple Cylinder Misfire Detected - [P0301](/codes/p0301): Cylinder 1 Misfire Detected - [P0128](/codes/p0128): Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature) - [P0217](/codes/p0217): Engine Coolant Over Temperature Condition - [P0420](/codes/p0420): Catalyst System Efficiency Below Threshold (Bank 1) ## Frequently asked questions ### Can I drive with a P0316 code? Usually yes for a short time, if the misfire clears within a minute and you are not losing coolant. Book a repair soon. If coolant level is dropping, white smoke appears at startup or the check engine light flashes, stop driving, because coolant in a cylinder can bend parts or damage bearings. ### What does misfire on startup mean? It means one or more cylinders failed to fire properly during the first 1,000 engine revolutions after starting, about the first minute of idling. The engine often smooths out once warm. The companion code, such as P0302 or P0300, tells you which cylinder to look at first. ### How much does it cost to fix P0316? Most P0316 repairs cost $120 to $1,100 at an independent shop. Spark plugs run $120 to $600, a leaking injector $250 to $1,100 and intake valve carbon cleaning $400 to $900. If a head gasket is letting coolant into a cylinder, expect $1,500 to $3,500 or more. ### Can a head gasket cause P0316? Yes, a leaking head gasket is one of the more serious causes. Coolant seeps into a cylinder while the car sits, so that cylinder misfires at the next start and often puffs white smoke. Steady coolant loss with no visible leak is the main warning. A shop confirms it with a combustion gas test. ### Why does my engine misfire only when cold? Cold engines need a strong spark and a well-mixed charge, so weak plugs or coils, leaking injectors and carbon on the intake valves show up first when cold. As parts warm and expand and fuel vaporizes better, the misfire fades. Coolant leaks into a cylinder also show up mainly after the engine has sat. ### Can I fix P0316 myself? You can check the basics yourself: note when the misfire happens, look at spark plug age and condition, check coil boots for moisture and watch the coolant level. Replacing plugs or a coil is a common home job. Injector leakage, carbon buildup and head gasket tests are best left to a shop. ### Does P0316 always come with another code? Usually, yes. P0316 only says when the misfire happened, at startup, not where. Most cars also store a cylinder-specific code such as P0301 through P0308, or P0300 for random misfires. If P0316 is stored alone, watch the misfire counters on a scan tool during several cold starts to find the cylinder. ### Will P0316 pass inspection? No, with the check engine light on the car fails an OBD-based emissions inspection in most states. Fix the cause, clear the codes and drive for several days, including cold starts, so the readiness monitors finish. Check that they show ready before you go back for a retest. ### Can carbon buildup cause P0316? Yes, on direct-injection engines heavy carbon on the intake valves is a known cause of cold-start misfires. The deposits soak up fuel and disturb airflow until the engine warms. A borescope inspection confirms it. Cleaning usually means removing the intake and blasting the valves with crushed walnut shell. ### Is P0316 covered by a recall or warranty? Some engines have had recalls, extended warranties or service bulletins for startup misfires, including coolant leaking into cylinders on certain models. Check your vehicle identification number on the NHTSA recall site and ask a dealer about bulletins. Powertrain warranty may also cover head gasket or engine damage on newer cars. ## Sources - [SAE J2012: Diagnostic Trouble Code Definitions](https://www.sae.org/standards/content/j2012_201812/) - [EPA: On-Board Diagnostics (OBD)](https://www.epa.gov/state-and-local-transportation/vehicle-emissions-board-diagnostics-obd) - [NHTSA: Check for recalls by VIN](https://www.nhtsa.gov/recalls) ## Other ignition and misfire codes - [P0303 Cylinder 3 Misfire Detected](https://diagxcar.com/codes/p0303) - [P0304 Cylinder 4 Misfire Detected](https://diagxcar.com/codes/p0304) - [P0305 Cylinder 5 Misfire Detected](https://diagxcar.com/codes/p0305) - [P0306 Cylinder 6 Misfire Detected](https://diagxcar.com/codes/p0306) - [P0307 Cylinder 7 Misfire Detected](https://diagxcar.com/codes/p0307) - [P0308 Cylinder 8 Misfire Detected](https://diagxcar.com/codes/p0308) - [P0320 Ignition/Distributor Engine Speed Input Circuit](https://diagxcar.com/codes/p0320) - [P0325 Knock Sensor 1 Circuit (Bank 1 or Single Sensor)](https://diagxcar.com/codes/p0325) - [P0326 Knock Sensor 1 Circuit Range/Performance (Bank 1 or Single Sensor)](https://diagxcar.com/codes/p0326) - [P0327 Knock Sensor 1 Circuit Low (Bank 1 or Single Sensor)](https://diagxcar.com/codes/p0327) ## Symptoms - [Why does my car shake at idle?](https://diagxcar.com/symptoms/car-shakes-at-idle) - [Why is white smoke coming from my exhaust?](https://diagxcar.com/symptoms/white-smoke-from-exhaust) - [Why is my car idling rough?](https://diagxcar.com/symptoms/rough-idle) - [Why is my car leaking coolant?](https://diagxcar.com/symptoms/car-leaking-coolant) ## Repair costs - [Spark plug replacement cost](https://diagxcar.com/cost/spark-plug-replacement): $120-$450 - [Fuel injector replacement cost](https://diagxcar.com/cost/fuel-injector-replacement): $300-$1,500 - [Head gasket replacement cost](https://diagxcar.com/cost/head-gasket-replacement): $1,400-$3,000 --- Source page: https://diagxcar.com/codes/p0316 Updated: 2026-11-03 General information, not a substitute for a qualified mechanic.