Pressure Testing
- After relieving fuel pressure, connect Fuel Pressure Gauge (07406-0040001 ) at 6mm service bolt location. Reconnect negative battery cable. Start engine and note fuel pressure. If vehicle will not start, has spark, and no fuel pressure is evident, inspect fuel pump main relay. See SYSTEM/COMPONENT TESTS article.
- Disconnect vacuum hose from pressure regulator and inspect for manifold vacuum. If vacuum is not present, check for restriction in vacuum port or hose. Plug vacuum hose and note fuel gauge reading. Gauge reading should be 36-41 psi (2.6-2.9 kg/cm2 ). Pressure should have risen slightly when vacuum hose was disconnected from pressure regulator.
- If pressure is higher than specified, inspect for pinched or clogged fuel return line between fuel rail and fuel tank. If no problem is found in fuel line, replace pressure regulator.
- If pressure is lower than specified, inspect for plugged fuel filter. If filter is not plugged, lightly pinch off fuel return line. If fuel pressure does not rise, replace fuel pump. If fuel pressure does rise, replace pressure regulator.