Can I keep driving with this symptom?

Briefly and gently, but injector faults rarely improve on their own and sustained running can damage the DPF, turbo or engine. Diagnose promptly.

Do I need to replace all injectors?

Not necessarily. Testing identifies the faulty unit(s); on high-mileage engines many workshops replace as a set to avoid repeat labour, but it is a judgement call.

Will a remanufactured injector fix it?

Yes — a properly remanufactured injector is rebuilt and bench-tested to OEM spec and carries a warranty, at a fraction of the new price.

Diesel Injector Problem — Fuel in the Engine Oil

A rising oil level or thin, diesel-smelling oil means unburnt fuel is washing past the pistons — chronic over-fuelling or leaking injectors are prime suspects.

Fix this issue

Most fuel in the engine oil issues in diesel engines are caused by failing fuel injectors.

✔Replace worn or leaking injectors
✔Restore performance and fuel economy
✔Prevent further engine damage

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Symptoms

Fuel in the Engine Oil

A rising oil level or thin, diesel-smelling oil means unburnt fuel is washing past the pistons — chronic over-fuelling or leaking injectors are prime suspects..

Diagnostic Tests

Injector leak-off test

Measures return flow from each injector with graduated bottles. One injector returning well above the others is internally worn.

Cylinder balance / contribution test

The ECU's per-cylinder correction values identify which injector is over- or under-fuelling.

Common Causes

Worn injector nozzle

Eroded nozzle orifices spray a poor pattern, so fuel burns incompletely or unevenly.

Sticking injector needle

Deposits or wear make the needle slow to open or close, upsetting delivery timing and quantity.

Post-injection / DPF regeneration cycles

Frequent interrupted regenerations add fuel to the oil; combine with injector testing for a full picture.

Repair Solution

Run a full diagnostic scan and record all stored fault codes before clearing anything.Test before replacing: leak-off, live data and balance tests isolate the faulty injector(s).Replace confirmed faulty injectors with bench-tested remanufactured units and code them to the ECU.Always fit new copper washers and seals when an injector is removed.

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