I have read, and read, and read. A learning process of course. I suppose everyone starts form the beginning, so thats where I'll begin. Bought a great ford truck. Love it. After starting it and the rpms would drop after 30 secs - 1 min the truck would stall unless you give it gas. It would eventually level out if you kept giving it a little. Fuel injected, not carbeurated. The truck would drive fine until it warmed up, then it would start choking and bucking. Took it to a shop, they said high pressure fuel had taken a dump. Okay, so I began the work myself.

Bought a new pump, installed it. New fuel filter. New fuel pump relay. Let me repeat, at the start of this the truck ran, and pretty well minus the hiccup.

Now upon completing the install, the truck will not start. There is no pressure in the lines. The in-tank pump is not getting power. The High-pressure pump is not getting power. My inertia switch is getting power. My fuel pump relay is getting power.

WHERE AM I LOSING POWER BETWEEN THE FUE PUMP RELAY AND THE INERTIA SWITCH?

So I am confused. I know the locations of all components, all components are new or known to be working... the problem is electrical (I believe) which makes it a nightmare! Any ideas? Don't really have anyone to brainstorm with and I think the guys at Advance are getting a little annoyed with me. I've got a Haynes book and a spirited will to win... but I'm struggling here.

I do have a question... when testing the wires going into the pigtail for the fuel pump relay I tested with the new relay in... no power. Put the old in and voila! Weird, right?

Another question, the inertia switch has a white button on top... when I press it it doesn't click or do anything. I can't tell if this is the way it is supposed to operate. That being said, I have not been in a collision or even driven the truck since it was running so I do not think it is bad. Also, no power in those cords going into it.

I just don't understand... if anyone has the time to help I would greatly appreciate it. I have read through a lot of information in the forum but nothing seems to apply to my specific set of circumstances. Is the EEC a culprit here? I know that it sends power to the relay.. so I have to assume it is working as well.

WHAT IS BETWEEN THE RELAY AND THE INERTIA SWITCH???

Thanks in advance!
Scott

 

Nothing but a wire inbetween them. I will give you a bit of advice; Don't unplug stuff and check for voltage. You will never find bad connections this way, you will always get 12v. The best way is to leave everything plugged in, and get a testlight with a sharp point and poke the wires. The circuit still has a load on it this way, and it makes the problem easier to find.

 

Okay, the part about the circuit is good to know. Haven't had my high pressure pump plugged up the whole time because I didn't figure it was necessary.

Another question; I was reading how a guy was troubleshooting a very similar problem and was turning the key with the wire poked. How long do I have after I turn the key to see if there is power in the circuit? One - two seconds? Or is power constant? For instance, if I were testing the fuel pp in the tank would I be able to walk to the back after I turn the key and check or is a helper necessary?

Thank you thank you!!

 

The computer primes the pumps for for a couple seconds and then looks for pulses from the distributor. If it doesn't see any pulses it stops the pumps. If you crank on it, the engine turns and the pumps keep running because the dist is sending pulses to the computer.

There is also a spot on the test port where you can ground a terminal to make the pumps run all the time. Here's a picture.