fuel problem
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
how do you KNOW there is no pressure past the FPR ????????????
how do you KNOW there IS pressure as far as the FPR ?????????
you know that this smacks of a bad pump, right?
If there IS pressure on the test gauge on the rails, there IS pressure past the FPR. period.
Fuel enters the FP-regulator, then rails or return or both then rails to injectors.
IF there IS pressure up to the FPR, there is NO WAY the FPR can dump all of the pressure if it were to get stuck and dump all to tank/return....there would be some residual tension that showed up on the gauge...20 psi or so, flickering unstable needle.
Yes, the FPR CAN get stuck, since it is only a plunger/disc under a spring. That disc can have a bad seat, the spring can break, the diaphragm can rupture or tear.
Smart money is on a bad "new" pump. Or bad electrical TO the "new" pump.
It should be easy enough to hear......
I've never heard a silent fuel pump.... <--(good oxymoron if you think it thru.)
they ALL make noise during the key ON for 2 seconds.....IF there is power to the pump AND the pump itself is good.
re: FP relay
fp electrical harness
See FSM FP relay diagnostics.
Good Luck
how do you KNOW there IS pressure as far as the FPR ?????????
you know that this smacks of a bad pump, right?
If there IS pressure on the test gauge on the rails, there IS pressure past the FPR. period.
Fuel enters the FP-regulator, then rails or return or both then rails to injectors.
IF there IS pressure up to the FPR, there is NO WAY the FPR can dump all of the pressure if it were to get stuck and dump all to tank/return....there would be some residual tension that showed up on the gauge...20 psi or so, flickering unstable needle.
Yes, the FPR CAN get stuck, since it is only a plunger/disc under a spring. That disc can have a bad seat, the spring can break, the diaphragm can rupture or tear.
Smart money is on a bad "new" pump. Or bad electrical TO the "new" pump.
It should be easy enough to hear......
I've never heard a silent fuel pump.... <--(good oxymoron if you think it thru.)
they ALL make noise during the key ON for 2 seconds.....IF there is power to the pump AND the pump itself is good.
re: FP relay
fp electrical harness
See FSM FP relay diagnostics.
Good Luck
Thread Starter
3rd Gear
Joined: Jul 2013
Posts: 3
Likes: 0
96 corvette.. im working on getting a pressure tester. hopefully tommorrow.but its getting to the rail if i disconnect the quick cont to fuel rail pressure is there gas squirts. fuel pump running push in valve past FPR nothing.....disconnect return line from rail not a drop of fuel...with pump hard wired bypassing harness. when i first installed the pump it lost pressure..wtf than heard gas spraying in the tank..it busted the hose that connects fuel pump to intake line busted it wide open..just FYI.possible FPR just stuck close not allowing any fuel thru. causing line to blow/no pressure. this is 91 corvette to 96 corvette lt1 install.
Thread Starter
3rd Gear
Joined: Jul 2013
Posts: 3
Likes: 0
i guess it possible wrong filter i got one for 91 corvette the l98 motel but the pump is l98 too.40 to 90 psi figured it was plently to run stock lt1..but i disconnect the inlet hose on fuel rail it sprays fuels can run pump fuel pumps out at good rate and thats past filter..motor did sit for 5 month before install..guess in gonna remove FPR see if fuel getting that far..idk its just wierd..
Drifting
Joined: Feb 2003
Posts: 1,976
Likes: 2
From: San Antonio Texas
I was gonna say... I put a new Hi Performance Pump in my '86 a couple of years ago. Confused me because I could hear it run. I discovered it was sucking instead of pushing fuel. It came with the 2 wires in the connector reversed.
