Fuel System Pressure Test

Fuel system pressure must be released any time a fuel line is to be disconnected.

1. Disconnect fuel inlet hose from throttle body and connect pressure testers C-3293 and C-4749 between fuel filter hose and throttle body.
2. Start engine and observe pressure gauge. Gauge should indicate 34-38 psi pressure. If indicated, reinstall fuel hose using a new clamp and torque to 10 in. lbs.
3. If fuel pressure is below 34 psi, install tester between fuel filter hose and fuel line and start engine. If pressure is now within specifications, replace fuel filter. If pressure does not increase, gently squeeze fuel hose. If pressure now increases, replace pressure regulator. If fuel pressure still does not increase, either the fuel pump is defective or the filter sock is obstructed
4. If fuel pressure exceeds 38 psi, remove fuel return hose from throttle body. Install a suitable length of hose to throttle body and place open end of hose into a clean container. Start engine and recheck fuel pressure. If pressure is now within specifications, check fuel return line for restrictions. If fuel pressure does not decrease to within specifications, replace pressure regulator.