P0313: Misfire Detected With Low Fuel

What does P0313 actually mean?

This code works alongside the regular misfire codes and sets when the computer detects misfire activity at the same time the fuel level sensor reports a low fuel level, typically below roughly an eighth of a tank. It exists to flag that the misfire may simply be fuel starvation from running low rather than a mechanical or electrical fault. Refueling and clearing the code is often enough to confirm which one it was.

The code sits in the ignition and combustion area and is reported by the misfire monitor. It names the circuit or the condition where the computer saw a reading outside its expected range. It does not name a failed part, and several genuinely different faults set this same code, which is the whole reason the causes below are ordered rather than listed.

What people usually notice

• Misfire that appears only when fuel is low
• Hesitation on hills or turns with a near-empty tank
• Misfire code alongside a low fuel warning
• Rough idle that improves after refueling

Why does P0313 set?

The causes below are ordered by how often they turn out to be the answer, cheapest and most common first. That order matters more than the list itself: the expensive component named in the code text is very rarely the first thing to replace, and working down from the top is what stops a ignition and combustion fault becoming an expensive guess.

Fuel level genuinely low, uncovering the fuel pump pickup on turns or hills is the one to rule out before anything else. This is by far the most common and cheapest explanation for this specific code.

The order worth checking on P0313

Start with freeze frame. Fuel level at the moment of the fault is the key value to check against the misfire event. That snapshot is taken at the instant the code set, and it is the single most useful piece of evidence you have, which is also why clearing the code before reading it is such a costly habit.

This code is diagnosed by watching values change rather than by reading the number again, so the tool has to stream live data and hold freeze frame. Live fuel level and fuel pressure data together confirm whether the misfire tracks fuel level or persists after refueling.

The order worth working in

• 1. Fuel level genuinely low, uncovering the fuel pump pickup on turns or hills: This is by far the most common and cheapest explanation for this specific code.
• 2. Failing fuel pump that struggles even with fuel present: A weak pump can misfire at low fuel level well before a healthy pump would.
• 3. Clogged fuel pump strainer or sock inside the tank: Sediment stirred up at low fuel levels can restrict flow at the pickup.
• 4. Damaged fuel level sending unit reporting a falsely low level: A bad sender can trigger this code even with adequate fuel in the tank.
• 5. Vehicle regularly driven near empty: Chronic low fuel driving accelerates wear on the pump and pickup.

Is it safe to drive with P0313?

Refuel as soon as reasonably possible, since the risk here is fuel starvation rather than a hard mechanical fault.

This is a severity 2 of 4 code. It will not usually strand you, but it will fail an emissions test while it is present, and the underlying fault rarely gets cheaper by being left alone.

What does it cost to ignore P0313?

Repeatedly running the tank low starves and overheats the fuel pump, which shortens its life and can eventually cause it to fail completely.

There is also the diagnostic cost of waiting. Freeze frame data, pending code history and the readiness monitor state all describe the fault as it was when it set, and all of it is lost the moment somebody clears the code to make the lamp go out.