904.0: no fuel pressure after new engine install

Title says it all. Put a new engine in my truck, and now have no pressure. None whatsoever when I press the valve on the fuel rail.

Can anyone tell me the location of the fuel pressure relay, and anything else I should look at? I already nuked out my ballast resistor- it's reading 1.8 ohms, which is within spec from what I've seen on here.

<yes, I already checked the search for this, and found nothing....>

The fuel pump relay is under the removable plastic cover on the passenger side of the engine compartment. This relay is bypassed when cranking. I think while cranking, the ignition switch has a set of contacts that give power to the fuel pump.

Thanks Paul.

Any input on where to start my troubleshooting?

Pinch off return hose (the front one) on the engine, and make sure the FP reg has not crapped out. Are you sure you do not have fuel flow? Have you removed your supply hose and turned on the key? If no flow, check fuel pump operation, stick your head under the Jeep and have someone turn on the key, should hear a buzz for about 2 sec. If no buzz, either no power, or pump is shot. If you have power & ground, it's probably your pump.

Of course I was sure I had no fuel flow. I removed the line, and nothing came out...

ended up replacing the FP after I tapped into the power supply right at the FP and jumpered off the battery, and got nothing.

I have PLENTY of fuel now. Still won't start. My battery is dead now, after all the attempting to crank with no fuel and all. I believe once I charge the battery, I should be good to go. If not, I'm going to get a noid light and make sure that I'm getting proper injection pulse.

Thanks for the help!

PaulJ said:

The fuel pump relay is under the removable plastic cover on the passenger side of the engine compartment. This relay is bypassed when cranking. I think while cranking, the ignition switch has a set of contacts that give power to the fuel pump.

Click to expand...

for the record, folks- the starter relay <next to the battery> has a terminal that goes to the fuel pump and runs it while you're cranking.