What it means
The 7th injector responds to commands but does not deliver expected fuel during regeneration. Coking on the nozzle or worn pressure regulation reduces flow.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Injector A in the exhaust aftertreatment system sprays fuel into the exhaust so active DPF regeneration can produce the heat needed to burn soot. P2698 sets when the injector responds to commands but its delivery does not meet the controller's expected performance.
Common causes
Most likely first.
- Coked nozzle restricts fuel delivery
- Fuel pressure to the dosing line out of tolerance
Symptoms
- Check-engine light
- DPF warning light
- More frequent or unsuccessful DPF regeneration
How to diagnose it
- Check freeze-frame data, DPF soot status, and regeneration history to establish when injector A's performance fault occurs.
- Inspect injector A and its exhaust-side nozzle for visible coking, damage, or leakage, following safe cool-down precautions.
- Check the dosing fuel supply and line for restriction, leaks, or signs of pressure-control trouble.
- Use a suitable scan tool and the manufacturer's procedure to compare commanded operation with measured dosing or pressure data.
- If the supply and control checks pass, test injector flow and pressure regulation against the manufacturer's specification.
Common fixes
- Clean or replace a restricted, coked injector A nozzle as permitted by the manufacturer.
- Repair a leak or restriction in the dosing fuel line.
- Service the fuel pressure regulation fault if measured pressure is outside the manufacturer's specification.
- Replace injector A if it fails the specified delivery test.
Can I keep driving?
Gentle driving may be possible, but avoid repeated short journeys and watch for a DPF warning or reduced power. Poor dosing can prevent regeneration, allowing soot to accumulate until the DPF needs service.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.