LT1 Fuel Pressure? Fuel Pump?
LT1 Fuel Pressure? Fuel Pump? Alright, changed the opti, the car was dying and wouldnt stay running. So tested the fuel pressure.
Key On: 8-10psi
Pump Key x10: Up to 30psi then drops to 0 in about 1/4 of a sec
Starting: Stays at about 30psi then it drops when key is off
I know the anti-bleed valve is bad on it but this is a stock fuel pump on a 388 stroker so I know its LEAN on WOT. The car started earlier and was stumbling really bad. T
The car will not start now and im getting plenty of spark. Anyone else agree?
I think its the fuel pump from the test, just wanna verify.
Key On: 8-10psi
Pump Key x10: Up to 30psi then drops to 0 in about 1/4 of a sec
Starting: Stays at about 30psi then it drops when key is off
I know the anti-bleed valve is bad on it but this is a stock fuel pump on a 388 stroker so I know its LEAN on WOT. The car started earlier and was stumbling really bad. T
The car will not start now and im getting plenty of spark. Anyone else agree?
I think its the fuel pump from the test, just wanna verify.
should be 40 minimun all times.....check regulator...or new pump...if you have a built motor a stock pump isnt enough...ive seen people run out a fuel with a stock motor and 75 shot
also the fuel filter is cheap insurance
also the fuel filter is cheap insurance
Had almost the exact same problem with mine. I had 12 PSI at ignition and trying to get the engine to turn over, it only had 12 PSI. It dropped off as soon as i turned the key off. Checked voltage at pump... 12V present?!? So i just bought a new pump....
I bought a walbro pump, and when i installed it, i noticed that the factory rubber hose connecting the pump to the hardline was split.
FYI...
I put an LT1 in an 86 chevy short wide truck. The fuel tank and sending unit is from an 87 model (factory equipped TBI). I NEVER thought about the fuel pressure difference between TBI (15 PSI)and MPI (40-50 PSI)...
In This picture you can see the "L" shaped split in the hose:
I bought a walbro pump, and when i installed it, i noticed that the factory rubber hose connecting the pump to the hardline was split.
FYI...
I put an LT1 in an 86 chevy short wide truck. The fuel tank and sending unit is from an 87 model (factory equipped TBI). I NEVER thought about the fuel pressure difference between TBI (15 PSI)and MPI (40-50 PSI)...
In This picture you can see the "L" shaped split in the hose:
Well guess what, I needed the 255lph pump newayz so I replaced it. Ended up being my MSD coil, I guess the high voltage output ate through the plastic where the coil wire connects so it was arching off of itself instead of going to my opti. So I put my spare stock one on it. Works fine.
YEA! Most the time I know these cars so well that I know what the problem is without even looking at it but this time I ruled the coil out because it is so new and it sparked.
