P0316: Engine Misfire Detected on Startup (First 1000 Revolutions)

What does P0316 mean?

P0316 concerns misfire within the first 1,000 revolutions after start. CARB requires a pending code here after the first exceedance of the emissions-relevant rate (later in the drive only after the fourth) and the warning light if it recurs at the next start. Ford sets P0316 in addition to the cylinder code; GM evaluates the start within P0300–P0308 without its own code. Typical causes are water in the plug wells (Mazda Tribute bulletin: blocked drain in the valve cover channel), coils that arc when cold and damp, injectors that drip after switch-off and over-rich starting – Ford traced cases on the 2.7 EcoBoost to engine software or leaking direct injectors.

The code tells you which monitor failed, not which part is broken. Test before replacing parts.

Symptoms

• Check engine light (usually with P0300/P030x)
• Rough running right after a cold start, then normal
• Delayed start, fuel smell at start

Common causes

• High Moisture or water in the plug wells, coils arcing when cold or damp
• Medium Leaking injectors (fuel drips after switch-off, over-rich start)
• Medium Worn or sooted spark plugs that only fire cleanly when warm
• Low Wrong temperature sensor value or engine software

Likelihood is a general estimate across vehicles; your make and model may differ.