Fuel Pressure: Notes
CAUTION:
High fuel pressure may be present in fuel lines and component parts. Relieve pressure before attempting to open system for testing or component replacement. Do not allow fuel to flow onto engine or electrical parts or allow an open flame in area while testing fuel system components.
Basic diagnosis of fuel system should begin with determining fuel system pressure. If fuel pump fails to run on fuel injected models, inspect power supply to main relay. If all power supplies are present (i.e. battery, ignition and starter switch during cranking), perform functional test of main relay. See WIRING DIAGRAMS and SYSTEM/COMPONENT TESTS - EFI articles.