Hello .. thanks for the donation .. much appreciated
I would be checking fuel pressure from pump and the regulator ... hope this helps .. let me know !!
Fuel Pump
An in-tank electric fuel pump delivers fuel to injector(s) through an in-line fuel filter. The pump is designed to supply fuel pressure in excess of vehicle requirements. The pressure relief valve in the fuel pump controls maximum fuel pump pressure.
On CPI fuel systems, pressure regulator is mounted to fuel metering body inside intake manifold. On TBI fuel systems, pressure regulator is mounted on throttle body.
When ignition switch is turned to ON position, control module turns on electric fuel pump by energizing fuel pump relay. Control module keeps pump on if engine is running or cranking (control module is receiving reference pulses from ignition module). If there are no reference pulses, control module turns pump off within 2 seconds after ignition is turned on.
Most models also include a second control path through the oil pressure switch which will turn the fuel pump on after the switch detects oil pressure. Cranking time will be longer if fuel pump does not receive current until oil pressure switch contacts close.
Fuel Pressure Regulator (CPI)
A constant fuel pressure of 54-64 psi (3.8-4.5 kg/cm2 ) is maintained by a factory preset, nonadjustable, spring loaded diaphragm contained within CPI assembly. Spring tension maintains a constant fuel pressure to injector regardless of engine load.
Fuel Pressure Regulator (TBI)
A constant fuel pressure of 9-13 psi (.6-.9 kg/cm2 ) is maintained by a factory preset, nonadjustable, spring loaded diaphragm contained within throttle body. Spring tension maintains a constant fuel pressure to injector regardless of engine load.
Fuel Pump Relay
When ignition switch is turned to ON position, control module turns electric fuel pump on by energizing fuel pump relay. Control module keeps relay energized if engine is running or cranking (control module is receiving reference pulses from ignition module). If there are no reference pulses, control module turns pump off within 2 seconds after key on.
As a back-up system to fuel pump relay, the oil pressure switch also activates fuel pump. The oil pressure switch is normally open until oil pressure reaches about 4 psi (.28 kg/cm2 ). If fuel pump relay fails, the oil pressure switch closes when oil pressure is obtained, and operates the fuel pump. Cranking time will be longer if fuel pump does not receive current until oil pressure switch contacts close. Oil pressure switch may be combined into a single unit with an oil pressure gauge sending unit or sensor.
Control module monitors fuel pump circuit between fuel pump relay/oil pressure switch and fuel pump, enabling control module to determine if fuel pump is being energized by fuel pump relay or oil pressure switch. A failure in this monitored circuit results in the setting of a related trouble code in control module memory.
Apr 6, 2009 at 8:11 PM
