P0313: Misfire Detected with Low Fuel

Quick answer

Code P0313 is triggered when the engine control module (ECM) detects a misfire specifically during low-fuel conditions. This means the issue is most noticeable when the fuel level drops below roughly a quarter tank, as the fuel pump struggles to maintain consistent pressure and delivery to the injectors.

How Low Fuel Triggers a Misfire and Sets P0313

The P0313 code is directly tied to a fuel-delivery problem that surfaces only when the tank is low. In most modern fuel-injected engines, the fuel pump sits inside the tank and relies on the surrounding fuel for cooling and consistent flow. When the fuel level drops, the pump can draw air along with fuel, causing intermittent starvation at the injectors. The ECM monitors crankshaft speed fluctuations through the crankshaft position sensor (CKP) and camshaft position sensor (CMP); when it detects uneven rotation that aligns with a misfire pattern, and the fuel level sensor reports a low reading, it logs P0313.

This scenario commonly occurs during hard acceleration or uphill driving at low fuel because the sloshing fuel exposes the pump inlet. The misfire may feel like a brief stumble or loss of power, and the check engine light often flashes during the event before staying on solid. Unlike random misfire codes (P0300-P0308), which can stem from ignition or mechanical issues, P0313 is uniquely linked to the fuel system's ability to supply consistent pressure under low-fuel conditions.

Several sensors play a role in confirming the condition. The fuel level sensor provides the low-fuel input, while the fuel rail pressure sensor (if equipped) may show dropping or erratic pressure during the misfire event. In vehicles without a dedicated fuel pressure sensor, the ECM infers pressure issues by correlating the misfire data with the fuel level and throttle position. This is why P0313 often appears alongside fuel pump-related codes or low fuel pressure warnings in scan tool data.

It's worth noting that a failing fuel pump or clogged fuel filter can also cause similar symptoms, but these issues typically trigger misfires at any fuel level. P0313 specifically isolates the problem to low-fuel scenarios, pointing strongly to a pump that's on its last legs or a tank design that doesn't support the pump properly when fuel is low. Over time, sediment in the tank can clog the pump inlet strainer, worsening the issue as the fuel level drops and the pump draws from the contaminated bottom of the tank.

Common Symptoms of P0313

P0313 commonly causes a noticeable stumble or hesitation during acceleration when the fuel tank is low, as the pump fails to keep up with demand. At idle, the engine may run rough or stall if the fuel starvation is severe enough. Many drivers also report a flashing check engine light during the misfire event, which then stays on as P0313 is stored in memory.

Typical Fixes for P0313

Repairs for P0313 typically involve replacing the fuel pump, cleaning or replacing the fuel filter, or addressing a clogged fuel tank strainer. In some cases, a failing fuel level sensor or wiring issue to the pump can also trigger the code. Repairs typically range from $400 to $1,200 depending on the cause ; see the full P0313 repair cost guide for a detailed breakdown.

Can You Still Drive With Code P0313?

You can usually drive with P0313 for a short period, especially if you keep the tank above a quarter full to avoid triggering the misfire. However, ignoring the issue risks sudden stalls or fuel pump failure, which can leave you stranded. If the misfire is frequent or severe, have the vehicle towed to prevent potential damage.

Details that improve the diagnosis

Watch the misfire counters at idle, during a gentle increase in engine speed and under load if a safe road test is possible. Compare fuel trims and note whether the fault follows temperature, moisture or a recent service. A cylinder pattern is often more useful than the code description alone.

Before clearing anything, record whether the code is current, pending, history or permanent. Save companion codes and freeze-frame conditions, then note recent repairs, a weak battery, weather changes and the exact moment the symptom appears. After a confirmed repair, clear only the erasable codes and complete the appropriate drive cycle. A permanent code normally clears only after the onboard monitor verifies that the fault is gone.

Related trouble codes

Information to record before any repair

Write down the exact code, its status and every companion code reported by a complete vehicle scan. Save the freeze-frame values, including engine speed, load, coolant temperature, vehicle speed, battery voltage and fuel trims when available. Note whether the warning appeared during a cold start, at idle, under acceleration, after refueling, in wet weather or immediately after other work. These details help separate an intermittent electrical problem from a repeatable mechanical or operating-condition fault.

Identify the exact year, make, model, engine, transmission and market version before using a wiring diagram or specification. Connector pinouts, monitor thresholds, component locations and test procedures can change within the same model line. Check current manufacturer service information and relevant technical service bulletins. A bulletin can improve the test sequence, but it should not be treated as proof that the same fault exists on every vehicle.

How to verify the repair

A warning light that stays off immediately after codes are cleared does not by itself confirm a repair. Recheck live data, repeat the operating condition that originally set the code when it is safe to do so, and confirm that no pending code returns. Some monitors need a specific drive cycle before they run. Permanent codes are normally removed by the control module only after it sees enough successful monitor results. If symptoms remain or the code returns, continue testing instead of replacing another part by guesswork.