Diesel fuel systems correct injection timing and quantity in closed loop, often with learning routines that run during suitable overrun phases. CARB requires a fault when such feedback control does not start within a manufacturer-defined time. P015E is the code of this kind for injection timing control: the closed-loop correction does not become active in time, or does not learn. It belongs to a family of similar codes – Ford's 2023 diesels, for example, set the sister code P016D when rail pressure adaptation has learned nothing after 300 s. No manufacturer document describing P015E itself, or its threshold, was found; the description rests on CARB and the sister code. Frequent causes are learning conditions that occur too rarely, software, or injectors outside tolerance.
Low severity. Can I keep driving?You can normally keep driving. If it affects the fuel level, do not trust the gauge and refuel earlier than usual.
Symptoms
- Check engine light on
- Usually no driving symptoms
- Possibly louder combustion noise or uneven running with unlearned injectors
Most likely causes
- Learning conditions (overrun phases, temperatures) met too rarely
- Control module software
- Injectors outside tolerance or unstable fuel pressure
- Injector wiring or sensors faulty
- Engine control module faulty
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It affects emissions.
What each character of P015E means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 1: Air and fuel
- 5E: Specific fault in that system
Frequently asked questions
Can I keep driving with code P015E?
You can normally keep driving. If it affects the fuel level, do not trust the gauge and refuel earlier than usual.
What causes code P015E?
The most common causes are: learning conditions (overrun phases, temperatures) met too rarely; control module software; injectors outside tolerance or unstable fuel pressure.
Related codes
- P016DExcessive Time To Enter Closed Loop Fuel Pressure Control
- P0125Insufficient Coolant Temperature for Closed Loop Fuel Control
- P249FExcessive Time To Enter Closed Loop Particulate Filter Regeneration Control
- P0149Fuel Timing Error
- P0087Fuel Rail/System Pressure - Too Low
Sources
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.