roadtrip120

iTrader: (29)

I have a ls1 , and it wont start.

Key on for start i only get 30 psi, my g/f's Ls1 is getting 58 psi when i turn the key on for start.

I already changed the fuel filter. The plugs are fouled out , so i will be changing them before i try to start it again.

Is the pump bad, or fuel pressure regulator, or wiring??

Any ideas

roadtrip120

iTrader: (29)

Update

I just changed out the plugs and started the car with starting fluid.

Fuel pressure is 50 psi at idle, then when i give it some gas it drops to 40 psi



Can anyone chime in, i'm thinking pump, but how do i test the regulator??

roadtrip120

iTrader: (29)

ok, well a little self taught lesson, answered my question.

Gm service manual is priceless.

Fuel System Dianosis

Step 2
1 - Turn key on , let fuel pump fully prime with fuel pressure gauge attached.
Is the puel pressure within in 55-60 psi??
No- Go to step 10

Step 10
1.Is the fuel pressure above 60psi?
No- Go to step 12

Step 12
1. Is fuel pressure about 0psi?
[b]Yes[b]Go to step 13

Step 13
Block off the return line going back to the tank. This can be done with a large vacume plug and a small hose clamp. Disconnect the plastic return line from the hard return pipe. About a foot back from the T-fitting is where the hard and plastic pipes join.
Does the fuel pressure rise above 60psi?Note-Make sure the fuel pressure does not exceed 72psi, it will damage the regulator)
Yes-Go to step 16
No- Go to step 7

Step 16
Replace fuel pressure regulator

Step 7
Replace fuel pump and check for leaks in tank, such as pump leak or regulator leaks.