Fuel System Pressure Test (SATURN)

CAUTION: Begin fuel system trouble shooting and diagnosis with checking fuel injection system pressure. High fuel pressure may be present in fuel lines and component parts. Relieve fuel pressure before disconnecting any fuel system components.

NOTE: Ensure battery is fully charged when performing test.

Remove air induction tube. Relieve fuel pressure. See FUEL SYSTEM PRESSURE RELIEF (SATURN) . Install fuel pressure gauge and bleed off any fuel in system into a container. Close fuel pressure gauge shutoff valve.
Turn ignition on. Using scan tool, command fuel pump on. Fuel pump should run for about one minute. Allow pressure to stabilize. Record maximum fuel pressure. Fuel pressure reading should be 40-55 psi (2.8-3.9 kg/cm² ).
Bleed fuel pressure and repeat test at least 2 more times. If during test, fuel pressure drops more than 8 psi (.56 kg/cm² ) during a 5 minute period, isolate fuel supply side of fuel system by closing off return side with fuel pressure gauge shutoff valve.
Using scan tool, command fuel pump on. Allow fuel pressure to stabilize. Record maximum fuel pressure. If fuel pressure remains stable, replace fuel pressure regulator. If fuel pressure bleeds off more than 8 psi (.56 kg/cm² ), check fuel inlet line and injectors for leaks, and check for faulty fuel pump. Repair as necessary.