1994 Buick Lesabre loosing fuel pressure when driving

JASONLIVES

MEMBER
1994 BUICK LESABRE

Engine Performance problem
1994 Buick Lesabre 6 cyl Front Wheel Drive Automatic

when driving the car will run great and then while watching an attached fuel pressure guage, the car will loose fuel pressure and stall, after sitting for awhile it will restart and fuel pressure is fine, have already replaced the fuel pump, can monitor all pids with my solus scanner, no codes mass air seem to be in spec, swapped out the fuel pump relay under the dash on the right kick panel. Still no change

1 Reply

JDL

MECHANIC
16,098 POSTS

Welcome to the forum, my info shows an oil pressure switch in the fuel pump circuit, wired in parallel to the relay, If there is oil pressure-- the switch is functional-- voltage to the switch, the pump should run even without the relay. The voltage to the o/p switch and load side of relay, comes from the same source. There is also a fuel pump prime connector, my info shows behind the battery, red wire with connector, nothing plugged into it. If you use a fused jumper wire from battery voltage to the connector, the pump should run. You don't need to use the key.