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Fuel System Residual Pressure

  1. Tee fuel pressure gauge into fuel supply line. Start engine and let it idle. Turn engine off. See FUEL PRESSURE SPECIFICATIONS  table.
  2. If residual fuel pressure is minimum or more, residual fuel pressure is okay. If residual fuel pressure is less than minimum, check fuel lines for leaks and repair as necessary. Check fuel injectors for leaks. See FUEL INJECTOR TEST  . Check fuel pump check valve for malfunction. See FUEL PUMP CHECK VALVE TEST  .
FUEL PRESSURE SPECIFICATIONS

Condition Specification
System Pressure
With Engine Idling (1) 55-61 psi (3.8-4.2 bar)
With Engine Idling (Warm) (2) 46-55 (3.2-3.8 bar)
Residual Pressure
Engine Cold (3) 32 psi (2.2 bar)
Engine Hot (3) 44 psi (3.0 bar)
(1) With fuel pressure regulator vacuum hose disconnected.
(2) With fuel pressure regulator vacuum hose connected.
(3) After 10 minutes.