P0316 – Engine Misfire Detected on Startup (First 1000 Revolutions)
What does P0316 mean?
The engine computer detected misfires during the first 1,000 crankshaft revolutions after startup. This code is specific to cold-start misfires and often appears alongside cylinder-specific misfire codes.
What causes P0316?
Listed from most to least common:
- 1Worn spark plugs that struggle when cold
- 2Weak ignition coils
- 3Leaking fuel injectors causing a flooded start
- 4Low fuel pressure at startup
- 5Carbon buildup on intake valves on direct-injection engines
- 6Vacuum leak that matters most when cold
- 7Low compression from valve or ring wear
- 8Faulty engine coolant temperature sensor causing wrong cold-start fueling
Code breakdown
Common symptoms
- Check engine light on
- Rough running for the first 30 seconds to a minute after a cold start
- Shaking or stumbling that smooths out as the engine warms
- Occasional hard starting
- Possible fuel smell at startup
How to diagnose
- 1Check for companion cylinder-specific codes such as P0301–P0306, which narrow the search considerably.
- 2Inspect spark plugs — cold-start misfire often reveals plugs near the end of their life.
- 3Test fuel pressure at startup and check whether it holds after shutdown. A pressure drop overnight suggests a leaking injector or check valve.
- 4On direct-injection engines, inspect intake valves for carbon buildup, a very common cause of cold-start roughness.
- 5Verify the coolant temperature sensor reads accurately when cold.
- 6Smoke-test for vacuum leaks.
Cold-start misfires can damage the catalytic converter over time. The condition often improves once the engine warms, which leads people to ignore it.
Common fixes and estimated costs
| Repair | Estimated cost |
|---|---|
| Replace spark plugs | $100–$350 |
| Replace ignition coil(s) | $150–$600 |
| Walnut-blast intake valve carbon cleaning | $400–$900 |
| Replace leaking injector | $200–$600 |
| Replace coolant temperature sensor | $60–$200 |
Costs are rough US estimates including parts and labor. Actual pricing varies significantly by vehicle, region, and shop rates.
Good to know
On direct-injection engines, carbon buildup on intake valves is a leading cause of P0316 and is not fixable with fuel additives, since fuel never touches the intake valves on those engines. Walnut blasting is the usual remedy.
Related codes
This information is provided for general reference only and may vary by manufacturer, model, and year. It is not a substitute for professional diagnosis or repair.