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Home >> Jaguar >> 1983 >> XJ-S >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - LUCAS/BOSCH P >> Adjustments >> Fuel Pressure Regulators
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Fuel Pressure Regulators

NOTE: Fuel pressure should only be adjusted after the complete system has been checked.
  1. Depressurize fuel system. Disconnect left-side cold start injector fuel supply hose from fuel rail. Connect a pressure gauge to fuel rail. Remove screws securing both pressure regulators to intake manifolds.
  2. Clamp off fuel line leading to left-bank pressure regulator inlet. Start engine. Loosen lock nuts on both pressure regulators. Turn adjuster bolt on right-bank pressure regulator until gauge reads 29.6 psi (2.1 kg/cm2 ).
  3. Remove clamp from left-bank pressure regulator inlet and transfer it to right-bank pressure regulator inlet. Turn adjuster bolt on left-bank pressure regulator until the gauge reads 29.6 psi (2.1 kg/cm2 ).
  4. Release clamp and ensure gauge reads 28.5-30 psi (2.0-2.2 kg/cm2 ). Tighten lock nuts on both pressure regulators. Turn off ignition. Depressurize fuel system and remove pressure gauge. Reconnect cold start injector line and test system for leaks.