Bronco Full Size L6-300 4.9L (1987)
2.
Connect a hose to line from fuel tank. Route hose into a suitable container.
3.
Disconnect the high pressure fuel pump electrical connector from body wiring harness.
4.
Locate and replace fuel pump relay with the modified relay, Fig. 13.
5.
Ground wire coming from relay to activate fuel pump, then measure fuel flow for 10 seconds. It may be necessary to block the fuel hose to
prime low pressure pump. With the outlet opened and under no back pressure on the outlet, this is normal.
6.
If fuel pump produces a minimum flow of 16 ounces of fuel in 10 seconds, the pump is operating properly. If there is no flow from the pump,
check electrical circuit, inlets for restrictions and then replace pump if necessary.
