Line Pressure
1. Close pressure gauge valve.
2. Operate the fuel pump.
3. Line pressure should not vary from a test value of 64.0-72.5 psi (4.5-5.1 bar) or a setting value of 66.9-69.7 psi (4.7-4.9 bar). Excessive line pressure may be caused by a blocked return pipe or faulty line pressure regulator. Insufficient pressure may be caused by insufficient fuel pump pressure, blocked fuel filter, leak in fuel pipe, or a faulty line pressure regulator.