Weak or failing fuel pump or low-pressure supply, giving poor pressure on a cold start; Blocked fuel filter or restricted fuel line; Faulty fuel rail pressure sensor or its wiring and connector for bank 2; Faulty fuel pressure regulator or pressure control valve (where fitted); Leaking or sticking injector on bank 2, or fuel leak in the rail or lines; High-pressure pump wear or fault on direct injection engines; Contaminated or poor-quality fuel.

P05FC

Cold Start Fuel Pressure Performance Bank 2.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
5: AreaVehicle speed, idle control and auxiliary inputs
FC: FaultThe specific fault in that area

What it means

P05FC means the engine control unit saw the fuel pressure on bank 2 fail to match its target during a cold start. The measured rail pressure was outside the expected range or did not build or hold as commanded. How bank 2 is supplied (separate rail, shared rail or separate pump) depends on the engine, so the exact layout varies by model.

Symptoms

Long cranking or hard starting when cold
Rough or unstable idle after a cold start
Hesitation or poor pickup while warming up
Engine management warning light on
Possible misfire or lean running on bank 2 until warm
Reduced power if the car enters limp mode

Possible causes

Weak or failing fuel pump or low-pressure supply, giving poor pressure on a cold startlikely
Blocked fuel filter or restricted fuel linelikely
Faulty fuel rail pressure sensor or its wiring and connector for bank 2possible
Faulty fuel pressure regulator or pressure control valve (where fitted)possible
Leaking or sticking injector on bank 2, or fuel leak in the rail or linespossible
High-pressure pump wear or fault on direct injection enginespossible
Contaminated or poor-quality fuelrare

How to diagnose

Read all stored and pending codes and note any other fuel, misfire or lean codes, then review the freeze frame data for temperature and rail pressure
Check for fuel leaks and inspect the fuel pressure sensor, pump and relay wiring and connectors on bank 2 for damage, corrosion or looseness
Check battery condition and supply voltage, as low voltage during cranking can affect pump output
Use live data to compare actual and target fuel pressure on a cold start, and note whether bank 2 differs from bank 1 where both are reported
Check the fuel pressure sensor reading with the key on and engine off against expected values for the model
Test low-pressure fuel supply pressure and volume using the manufacturer's procedure and specification
Check the fuel filter service history and condition, where it is serviceable
Test the pressure regulator or control valve and injector operation, following the model-specific procedure

How to fix

Repair or replace the fuel pump, relay or wiring if supply pressure or voltage is low
Replace a blocked fuel filter and clear any restricted lines
Replace a faulty fuel rail pressure sensor or repair its wiring and connector
Replace a faulty pressure regulator or pressure control valve
Repair fuel leaks and replace leaking or sticking injectors on bank 2
Replace a worn high-pressure pump if testing confirms it is the cause

Can I keep driving?

Medium severity

The car can usually be driven for a short time, but book it in soon as low fuel pressure can cause stalling, poor running and, on some engines, damage from lean running. Stop driving if it stalls, loses power badly or you smell fuel.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.