48-4391 — Technical Research
Zexel 48-4391 (484391 / Z484391) injector for the Nissan 2.2 Di/dCi YD22DDTi in the Almera II, Almera Tino and Primera. Verify the injector setup in Nissan Consult on fitment. Remanufactured, calibrated, 12-month warranty. Key symptoms: Rough idle / vibration; Hard starting; Loss of power / limp mode; Black smoke. Common failure modes: Internal wear / high back-leakage; Nozzle coking / poor spray pattern; Water-in-fuel corrosion.
Zexel 48-4391 2.2 Di/dCi Diesel Injector (Nissan Almera, Almera Tino, Primera YD22DDTi)
Zexel 48-4391 (484391 / Z484391) injector for the Nissan 2.2 Di/dCi YD22DDTi in the Almera II, Almera Tino and Primera. Verify the injector setup in Nissan Consult on fitment. Remanufactured, calibrated, 12-month warranty. Key symptoms: Rough idle / vibration; Hard starting; Loss of power / limp mode; Black smoke. Common failure modes: Internal wear / high back-leakage; Nozzle coking / poor spray pattern; Water-in-fuel corrosion.
A leaking or out-of-calibration injector unbalances cylinder fuelling, felt as a shake at idle.
Excess back-leakage bleeds rail/line pressure during cranking, causing long or failed starts.
Out-of-range delivery or pressure deviation triggers a torque cut and limp home.
Poor atomisation or a dribbling nozzle over-fuels the cylinder.
Cylinder-specific injector, balance or fuel-metering fault codes are logged.
- InstallationVerify the injector setup requirement in Nissan Consult; many early YD22 Di applications require no electronic injector coding.
- InstallationRenew the copper combustion washer and leak-off seals; torque the clamp/nut to manufacturer spec.
- MisdiagnosisRead live back-leakage and per-cylinder contribution data to confirm the weak cylinder before removal.
- TestingBench-test across delivery and back-leakage points and verify spray pattern before refit.
- WarningConfirm fitment by OE number and engine code before ordering; injector sub-variants are not always interchangeable.
What is injector 48-4391?+
48-4391 is a Zexel diesel injector diesel injector for the Nissan 2.2 Di / dCi (YD22DDTi). It is supplied remanufactured, bench-tested and calibrated to OEM specification.
Which vehicles use 48-4391?+
It is fitted to the Nissan 2.2 Di / dCi (YD22DDTi) — including Nissan Almera II (N16) 2.2 Di / dCi (YD22DDTi); Nissan Almera Tino (V10) 2.2 Di / dCi (YD22DDTi); Nissan Primera (P11/P12) 2.2 Di / dCi (YD22DDTi); Nissan X-Trail (T30) 2.2 dCi (YD22DDTi). Confirm fitment by OE number and engine code.
What type of injector is 48-4391?+
It is a Zexel Diesel Injector. Always confirm the OEM markings on the injector body before fitting.
Does 48-4391 need coding when fitted?+
Verify in Nissan Consult — many early YD22 Di applications run without electronic injector coding. Confirm for your specific build before road test.
What are the symptoms of a failing 48-4391?+
Common signs are rough idle and vibration, hard starting, power loss or limp mode, black smoke and an engine-management light.
What causes these injectors to fail?+
Most failures come from poor fuel filtration, contamination and water in the fuel leading to wear, high back-leakage and nozzle coking. Fix the cause before fitting replacements.
Is a remanufactured 48-4391 as good as new?+
A properly remanufactured injector is stripped, fitted with new wear parts, reassembled and recalibrated on a common-rail test bench to OEM tolerances, then supplied with a warranty.
Should I replace one injector or the full set?+
Replace the confirmed faulty injector first. On high-mileage engines fitting a matched set reduces the chance of a repeat fault, but it is not mandatory if the others test within spec.
Do you bench-test the injector before dispatch?+
Yes. Every unit is tested for delivery, back-leakage and spray pattern on a calibrated common-rail tester before it leaves us.
Is delivery and warranty included?+
Yes — the price includes free UK delivery and a 12-month warranty.
Which Nissan models use the 48-4391 injector?+
The Nissan 2.2 Di/dCi YD22DDTi in the Almera II (N16), Almera Tino, Primera and X-Trail (T30). Confirm the YD22DDTi engine code before ordering.
Does the Zexel 48-4391 need coding?+
Verify in Nissan Consult — many early YD22 Di applications run without electronic injector coding. Always renew the copper washer and bleed the system on fitment.