Misfire Detected with Low Fuel
Code P0313 indicates the engine is misfiring when fuel level is low, typically below 1/4 tank. This occurs because low fuel can expose the fuel pump intake to air, causing inadequate fuel delivery and combustion problems.
What You Might Notice
- Check Engine Light illuminated
- Rough or shaky engine idle
- Hard starting or no-start condition
- Hesitation during acceleration
- Loss of engine power
Most Common Causes
- 1
Low fuel level
Fuel level below 1/4 tank exposes the fuel pump intake to air, causing inadequate fuel delivery to the injectors and resulting in misfires.
- 2
Failing fuel pump
A weak or failing fuel pump cannot maintain adequate pressure, especially when fuel level drops, leading to lean misfire conditions.
- 3
Clogged fuel filter
A dirty or blocked fuel filter restricts fuel flow to the engine, causing low fuel pressure and lean misfires, particularly noticeable at low fuel levels.
- 4
Faulty fuel pressure regulator
A malfunctioning regulator cannot maintain proper fuel system pressure, resulting in inadequate fuel delivery and engine misfires.
How to Diagnose It
- 1
Check Low fuel level — Fuel level below 1/4 tank exposes the fuel pump intake to air, causing inadequate fuel delivery to the injectors and resulting in misfires.
- 2
Check Failing fuel pump — A weak or failing fuel pump cannot maintain adequate pressure, especially when fuel level drops, leading to lean misfire conditions.
- 3
Check Clogged fuel filter — A dirty or blocked fuel filter restricts fuel flow to the engine, causing low fuel pressure and lean misfires, particularly noticeable at low fuel levels.
- 4
Check Faulty fuel pressure regulator — A malfunctioning regulator cannot maintain proper fuel system pressure, resulting in inadequate fuel delivery and engine misfires.
How to Fix It
- 1
Refill fuel tank
Add fuel to bring the tank above 1/4 full and clear the code. If the code returns immediately, proceed to fuel system diagnostics.
- 2
Replace fuel filter
Remove and replace the fuel filter following manufacturer specifications. A clogged filter is a common cause of low fuel pressure and misfires.
- 3
Test and replace fuel pump
Use a fuel pressure gauge to test pump output. If pressure is below specification, replace the fuel pump assembly in the fuel tank.
- 4
Inspect fuel pressure regulator
Check the regulator for proper operation and fuel leaks. If faulty, replace it to restore correct fuel system pressure.
Need a deeper diagnosis?
Search for related repair guides or browse by system.