Faulty or sticking cylinder 5 fuel injector, or one with worn or contaminated internals; Wiring or connector fault in the cylinder 5 injector circuit, such as high resistance, corrosion or chafing; Low or unstable fuel rail pressure from a weak pump, regulator or fuel supply restriction; Crankshaft or camshaft position sensor signal fault or timing reference error; Mechanical timing fault, such as a stretched chain, belt slippage or incorrect timing; Poor fuel quality or contamination affecting injection response; Outdated or faulty ECU software or calibration where a known fault is documented for the engine.

P01D3

Cylinder 5 Injection Timing Performance - Over Retarded.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
1: AreaFuel and air metering
D3: FaultThe specific fault in that area

What it means

P01D3 is a generic powertrain code meaning the engine control unit has detected that the fuel injection timing for cylinder 5 is later than commanded, or later than the strategy expects. The ECU compares the actual or estimated injection event against its target and sets the code when the retard exceeds the allowed limit. It is most often seen on diesel and direct injection engines with six or more cylinders, but the exact monitoring method depends on the engine.

Symptoms

Engine warning light on
Rough running or misfire, mainly on cylinder 5
Noticeable loss of power or hesitation
Hard starting or extended cranking
Increased diesel knock or uneven idle
Higher fuel consumption or visible smoke

Possible causes

Faulty or sticking cylinder 5 fuel injector, or one with worn or contaminated internalslikely
Wiring or connector fault in the cylinder 5 injector circuit, such as high resistance, corrosion or chafinglikely
Low or unstable fuel rail pressure from a weak pump, regulator or fuel supply restrictionpossible
Crankshaft or camshaft position sensor signal fault or timing reference errorpossible
Mechanical timing fault, such as a stretched chain, belt slippage or incorrect timingpossible
Poor fuel quality or contamination affecting injection responsepossible
Outdated or faulty ECU software or calibration where a known fault is documented for the enginerare

How to diagnose

Read all stored and pending codes and the freeze frame data, noting engine load, rail pressure, temperature and speed when the fault set
Check for related codes covering other injectors, rail pressure, crank or cam sensors, or misfires, as these point to the root cause
Inspect the cylinder 5 injector wiring and connector for damage, corrosion, loose pins and oil or coolant contamination
Check the fuel level, fuel quality and fuel filter condition, and look for air or water in the fuel
Compare live data for rail pressure actual versus requested, and look at injector correction or balance values for cylinder 5 against other cylinders
Check crank and cam sensor signals and their correlation using a scope or the live data, following the manufacturer procedure
Test the cylinder 5 injector electrical resistance and perform an injector leak-off or flow test where the engine design allows
Verify mechanical timing if signals or correlation look wrong, using the model-specific procedure

How to fix

Repair or replace damaged wiring or connectors in the cylinder 5 injector circuit
Replace the cylinder 5 injector if testing shows it is faulty, and code or adapt it to the ECU as the manufacturer requires
Replace the fuel filter, drain contaminated fuel and correct supply problems, then repair any faulty pump or pressure regulator
Replace a faulty crank or cam position sensor and clear any related faults
Correct mechanical timing faults by renewing worn timing components and setting timing to specification
Update the ECU software only where the manufacturer lists an outdated calibration as a cause for this fault

Can I keep driving?

Medium severity

Short, gentle driving is usually possible, but have it checked soon because a faulty injector or timing problem can worsen and damage the engine or catalyst. Stop driving if there is heavy misfire, flashing warning lights, severe knocking or smoke.

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