Fuel Pressure Regulator – Jaguar X-Type – 4S4Q9G586AA

Restore correct fuel rail pressure and stable engine running on your Jaguar X-type with this direct-replacement fuel pressure regulator — also known as the FPR, fuel pressure regulator valve or rail pressure regulator. Built to OEM specification and matching part numbers 4S4Q-9G586-AA, 9307Z501C, 1329098, 9307Z523B and 9307Z509B. Also fits equivalent Citroën, Dacia and Ford models.

Common signs of failure

A failing fuel pressure regulator commonly causes hard starting when hot, rough idle, hesitation under acceleration, poor fuel economy, and fault codes P0089, P0190, P0191 or P0192. On some vehicles you'll see fuel leaks at the regulator body, or a strong fuel smell under the bonnet. Common-rail diesels with stuck regulators drop into limp mode under load. Petrol direct-injection engines may also show a rough cold start or misfire codes.

Fitment notes

Direct-fit replacement, threaded into the fuel rail or pump body. Relieve fuel pressure before removal and have rags ready to catch residual fuel. Replace any sealing O-rings supplied. After fitting, cycle the ignition to prime, clear codes and test for leaks before driving. Standard 2 pin connector.

Frequently asked questions

Is this the same as a fuel pressure sensor?

No — the sensor measures rail pressure and reports to the ECU. The regulator physically controls rail pressure. Both can fail and produce similar fault codes, so confirm with live data before ordering.

Can I drive with a failing FPR?

Short distances yes, but unregulated fuel pressure damages injectors over time on common-rail diesels and causes excess emissions on petrol engines. Replace promptly.

Do I need to code or programme the new regulator?

No — it's a passive hydraulic component. The ECU re-learns rail pressure within a few minutes of running.