Faulty fuel injector for cylinder 6, such as a sticking nozzle or internal leakage; Wiring harness damage or poor electrical connection at the cylinder 6 injector; Failed injection timing control solenoid or spool valve inside the high-pressure fuel pump; Contaminated engine oil affecting the hydraulic timing advance mechanism; Engine control module software calibration issue or internal fault; Low fuel pressure or restricted fuel supply affecting injection timing; Worn camshaft or crankshaft position sensor reluctor wheel causing timing signal errors

DTC codes / P01xx · Fuel and air metering / P01D5

P01D5Cylinder 6 Injection Timing Performance - Over Retarded

Q: What does code P01D5 mean?

Cylinder 6 Injection Timing Performance - Over Retarded. P01D5 indicates that the engine control module has detected the fuel injection timing for cylinder 6 is retarded beyond the commanded value during operation. The computer compares the actual injection event timing to the desired timing and sets this code when the deviation exceeds a calibrated threshold, typically under specific load and temperature conditions.

P01D5 indicates that the engine control module has detected the fuel injection timing for cylinder 6 is retarded beyond the commanded value during operation. The computer compares the actual injection event timing to the desired timing and sets this code when the deviation exceeds a calibrated threshold, typically under specific load and temperature conditions.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaFuel and air metering

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Rough idle or misfire sensation, especially when the engine is cold
Reduced engine performance or sluggish acceleration
Increased fuel consumption due to inefficient combustion
Occasional engine stumble or hesitation during light throttle
Elevated exhaust emissions or a fuel odor from the tailpipe

Common causes, most likely first

Faulty fuel injector for cylinder 6, such as a sticking nozzle or internal leakage
Wiring harness damage or poor electrical connection at the cylinder 6 injector
Failed injection timing control solenoid or spool valve inside the high-pressure fuel pump
Contaminated engine oil affecting the hydraulic timing advance mechanism
Engine control module software calibration issue or internal fault
Low fuel pressure or restricted fuel supply affecting injection timing
Worn camshaft or crankshaft position sensor reluctor wheel causing timing signal errors

How to diagnose and fix it

Connect a scan tool and verify the code is current, then check for any related pending or history codes
Inspect the cylinder 6 injector connector and wiring for corrosion, chafing, or loose pins
Perform a fuel injector balance test or cylinder contribution test to compare cylinder 6 to others
Check engine oil condition and level, as degraded oil can affect hydraulic timing components
Test fuel pressure and volume to rule out a supply issue before replacing parts
Swap the cylinder 6 injector with a known-good injector from another cylinder and see if the code follows
If the fault persists, diagnose the injection timing control solenoid and ECM calibration per manufacturer procedures

Before you replace the cylinder 6 injector

A dirty or failing injector is the most common cause, but a simple connector wiggle test often reveals a chafed wire that mimics an injector failure.
This code can be set by low oil pressure or sludged oil because many modern injection timing systems rely on engine oil hydraulics to adjust timing.
Swapping the injector to another cylinder is a quick diagnostic step that prevents unnecessary replacement of the wrong part.
Some vehicles require an ECM reflash or calibration update to correct a software-induced timing error before any hardware is replaced.
A misfire code for cylinder 6 may accompany P01D5, but the misfire could be the cause rather than the result, so always diagnose both together.

Can I keep driving with P01D5?

You can usually drive the vehicle short distances to a repair shop, but avoid heavy acceleration or towing because retarded injection timing can lead to incomplete combustion and overheating of exhaust components. If the engine runs very rough or stalls, stop driving and have it towed.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.