New fuel pump- now won't stay running!

After a few months at the dealer for a recall, I was having some hesitation and starting problems. I've had to "cycle the key" for a while, and figured the fuel pump might finally be on it's way out.

Tested with a fuel pressure gauge, and with the old pump it would take a while to get up to ~49 psi (long crank) and wouldn't stay there, so I ordered and installed a bosch replacement. Ran better, but would still not hold pressure once the key was off, leading to long starts again. So I thought I would replace the entire assembly (strainers, pressure regulator, etc.) and picked one up. Placed the bosch pump in the new assembly and tryed to start it.

So now it will build pressure after a few cycles of the key (I can hear the pump activate, then start almost immediately! Problem is it dies within 5 seconds. It's almost as if it shuts off fuel flow once the engine starts.

So should I order a whole new assembly or is something else happening here. I tried swapping the pump relay, no difference.

This might sound dumb but check the hose between the pump and the assembly. I just had a problem with mine. Bled off immediately after shutoff. Found that hose completely bypassing fuel back to the tank.

What year?

Firing up then sputtering out at 5 seconds sounds like a disconnected ballast resistor. Damn thing got me once, I must have accidentally unplugged it while doing a bunch of work. I was so frustrated, going back through all the work I did trying to figure out where I screwed up.

1t's a 97, if that helps.

Hook a fuel pressure guage up and watch the dial during idle. See what happens.

Fuel problems can be at the rail and injector end as well. I would check the fuel pressure. What recall would they have done on a 97? Was it putting a shiled in the intake? Maybe something was knocked loose.

I see no mention of the fuel filter. Have you replaced that? I could imagine an old and plugged fuel filter having such an effect.

Reddleman said:

So now it will build pressure after a few cycles of the key (I can hear the pump activate, then start almost immediately! Problem is it dies within 5 seconds. It's almost as if it shuts off fuel flow once the engine starts.

So should I order a whole new assembly or is something else happening here. I tried swapping the pump relay, no difference.

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Do you have a Sentry Key Immobilizer System?