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Home >> Saab >> 1990 >> 900 SPG, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Testing >> Fuel System >> Fuel Pressure Check >> Fuel Line Pressure
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Fuel Line Pressure

  1. Disconnect banjo coupling at inlet to fuel injection manifold. Connect a fuel pressure gauge using existing seals. Ensure pressure gauge hangs vertically.
  2. Turn ignition off. Remove fuse No. 30 on 900 models. Remove fuse No. 14 and No. 22 from 9000 models. Connect a jumper lead between fuse No. 27, 28, or 29 and slot of fuse No. 30 for 900 models. Connect the jumper between fuse No. 22 and slot of fuse No. 14 on 9000 models. This will provide current to the fuel pump. Turn ignition on.
  3. Line pressure should rise to approximately 36 psi (2.5 kg/cm2 ). If line pressure is too high, go to next step. If line pressure is too low, go to step 5).
  4. Turn ignition off. Disconnect fuel return line from pressure regulator and blow through line. If line is open, pressure regulator is defective and should be replaced. If line is blocked, remove blockage, or replace with a new return line. Check one-way valve at tank, and retest system.
  5. Check fuel level, do not rely on fuel gauge. Check for fuel system leaks. Check fuel pressure regulator. See FUEL PRESSURE REGULATOR  test. If proceeding to FUEL PRESSURE REGULATOR test, do not remove fuel pressure gauge.