P0313 Code: Causes, Symptoms, Diagnosis & How to Fix It
What Does P0313 Mean?
P0313 means “Misfire Detected With Low Fuel.” It is a generic OBD2 powertrain trouble code indicating that the engine computer detected a misfire while the fuel level or fuel delivery condition was low.
Unlike cylinder-specific codes such as P0301 or P0312, P0313 does not identify one particular cylinder. The problem may occur because the fuel level becomes low enough for the fuel pump to have difficulty maintaining consistent fuel delivery.
However, P0313 does not always mean that simply adding fuel will permanently solve the problem. A weak fuel pump, restricted fuel filter, low fuel pressure, injector problem, wiring fault, or air/fuel issue can also contribute to the code.
P0313 Code Symptoms
Common symptoms of a P0313 code include:
Check Engine Light
Rough-running engine
Engine hesitation
Stumbling during acceleration
Reduced engine power
Hard starting
Engine may stall
Poor acceleration
Misfire under low-fuel conditions
Possible difficulty restarting after running very low on fuel
The exact symptoms depend on the vehicle and the severity of the fuel-delivery problem.
Common Causes of P0313
Several problems can trigger P0313.
1. Very Low Fuel Level
The simplest cause is allowing the fuel level to become extremely low. When fuel is near empty, the pump may not maintain consistent fuel pickup during acceleration, cornering, or other driving conditions.
2. Weak Fuel Pump
A failing fuel pump may have difficulty maintaining adequate pressure, particularly when fuel level is low.
3. Clogged Fuel Filter
A restricted fuel filter can reduce fuel flow and cause the engine to run lean or misfire.
4. Low Fuel Pressure
A fuel pressure regulator, pump, restriction, or another fuel-system problem can prevent the engine from receiving enough fuel.
5. Faulty Fuel Injector
A clogged or malfunctioning injector can disrupt the air-fuel mixture and contribute to a misfire.
6. Fuel Pump Wiring Problems
Damaged wiring, poor electrical connections, or connector problems can prevent the fuel pump from operating correctly.
7. Vacuum or Intake Leak
A significant intake leak can create a lean air-fuel mixture and contribute to misfire symptoms.
8. Ignition or Engine Problems
Spark plugs, ignition coils, compression problems, airflow sensors, and other engine components can also contribute to a misfire.
How to Diagnose P0313
The best approach is to determine whether P0313 was caused by simply running the fuel level too low or whether there is an underlying fuel or engine problem.
Step 1: Check the Fuel Level
Start with the simplest possibility. Add sufficient fuel and see whether the engine returns to normal operation.
Do not assume the problem is fixed just because the Check Engine Light turns off.
Step 2: Scan for Additional Codes
Use an OBD2 scanner to check for stored and pending trouble codes. Additional fuel, injector, airflow, or misfire codes can help narrow down the problem.
Record the freeze-frame information when available.
Step 3: Check Fuel Pressure
Measure fuel pressure according to the manufacturer's specifications. Compare the actual pressure with the required pressure for the vehicle.
Low pressure can point toward a weak pump, restriction, regulator problem, or another fuel-delivery issue.
Step 4: Inspect the Fuel System
Check the fuel pump wiring, connectors, fuel filter, and accessible fuel-system components for damage or poor connections.
Step 5: Check for Intake Leaks
Inspect vacuum hoses and intake connections. A smoke test can help locate an intake leak that is not visible during a basic inspection.
Step 6: Check the Ignition System
Inspect spark plugs, ignition coils, plug wires, and related wiring if the misfire continues after fuel delivery has been checked.
Step 7: Check Injectors
Test injector operation and inspect injector wiring. A restricted or malfunctioning injector can create an uneven air-fuel mixture.
Step 8: Check Engine Data
Use scanner live data to review fuel trims, airflow readings, and other relevant engine parameters. If necessary, compression testing can help rule out an internal engine problem.
How to Fix P0313
The correct repair depends on the cause. Possible repairs include:
Add fuel if the tank was simply too low
Replace a weak fuel pump
Replace a clogged fuel filter
Repair low fuel pressure problems
Repair fuel pump wiring or connectors
Clean or replace a faulty fuel injector
Repair vacuum or intake leaks
Replace worn spark plugs
Replace a faulty ignition coil
Repair engine compression or mechanical problems
Repair airflow or sensor problems when testing confirms the fault
After the repair, clear the trouble code and test drive the vehicle under normal operating conditions.
Is P0313 Serious? Can You Drive With It?
P0313 should not automatically be treated as a major engine failure, especially if the vehicle was driven with an extremely low fuel level.
However, continued driving with a fuel-delivery problem can cause repeated misfires, stalling, poor performance, and potentially additional component damage.
If the Check Engine Light is flashing, the engine is shaking severely, the vehicle is losing significant power, or it repeatedly stalls, avoid driving until the problem is diagnosed.
If the fuel tank was nearly empty and the vehicle runs normally after refueling, monitor it closely and scan for any remaining or returning codes.
P0313 vs P0312
P0313 means Misfire Detected With Low Fuel, while P0312 specifically identifies a misfire in cylinder 12.
P0313 is therefore more closely associated with fuel-level or fuel-delivery conditions, while P0312 points to a specific cylinder that is misfiring.
P0313 vs P0300
P0300 means Random/Multiple Cylinder Misfire Detected, while P0313 indicates a misfire associated with low-fuel conditions.
A vehicle can potentially have both codes if low fuel or a fuel-delivery problem contributes to multiple-cylinder misfires.
Frequently Asked Questions
What does P0313 mean?
P0313 means Misfire Detected With Low Fuel.
Can adding fuel fix P0313?
It can if the code was caused by running the fuel level extremely low. If the code returns after refueling, further diagnosis is needed.
Can a bad fuel pump cause P0313?
Yes. A weak fuel pump can cause inadequate fuel delivery and contribute to a misfire when the fuel level is low.
Can a clogged fuel filter cause P0313?
Yes. A restricted fuel filter can reduce fuel flow and contribute to low fuel pressure and misfire conditions.
Is P0313 safe to drive with?
If the vehicle is running normally after refueling, a short trip may be possible. If there is a flashing Check Engine Light, severe shaking, stalling, or major power loss, avoid driving until the cause is diagnosed.
