Have you tried swapping the asd relay?
Check both voltage and ground at the (coil) terminals at the relay. Run a small wire into the terminals then put the relay in to test it. You should have good constant 12V/ground(ignition on). If you have your fingers on the relay you should be able to feel it chatter.

 

HeyYou and everyone else who responded,

Thanks for all your support this weekend. My work shift starts tonight, but I will be back on the Dakota no later than Friday. I have some tools coming (good excuse to buy some new tools!), including what I need to separate the fuel line from the fuel rail. I will measure the OD of the nipple and get a fitting. I have seen where speed shops sell nitrous fittings that should work as an adapter for my fuel pressure gauge. Have a great week!

 

Thanks so much for taking the time to help!

Yes, swapping relays is one of the first things that I did - forgot to mention that. The problem stays with the socket, not the relay. Every relay will chatter in that spot. I did put some leads in the relay socket with the relay in place as you described. With the key on, no crank, there is a full 12VDC. With a load (cranking, lights on), the voltage sinks to approximately 10 VDC, which is a good result for a load test.

I think the problem is with the grounding provided by the PCM - that is what is used to switch the control relay. When I measured the ground side of the control circuit to the negative battery post while cranking, the signal was all over the place. I was reading DCR, so the active device in the PCM that switches that ground is probably messing with my readings. It should just act as a short to ground, though.

I will revisit all of this Friday after my work shift is over. Please continue to suggest solutions - it helps with the tunnel vision.

 

So my work week is over and I am back on the Dakota. I paired my scanner today and found no codes. The truck started and ran rough, then died. I started it again and it ran rough again and died. It is still a little dark and chilly outside. I will head out there in a little bit and start checking around again. I did not hear the ASD chattering this morning.

UPDATE: Well, it isn't getting much warmer today, so I went out to the truck and tried to start it again with the same luck:

1. Starting, running rough briefly, then stalling
2. No chattering ASD relay
3. No codes

I am beginning to suspect a fuel starvation issue, compounded by an unrelated intermittent electrical issue. O Joy. I do have a tool to separate the quick disconnect fuel line now. I have read that pulling the fuel pump relay and cranking the motor will bleed off the fuel pressure, so that is what I will attempt next. Then, I will have to order some type of a fitting to adapt my pressure gauge to the incoming fuel line.

UPDATE: Ordered fittings that should work, will revisit this page tomorrow. I am looking forward to checking fuel pressure - that should narrow down the list of probable causes significantly.

 

My adapters came in and look like they will fit; the nipple may be too long. However, I think I will need a T-fitting and a female quick disconnect as well so that I can test pressure inline. I can test the pump/check valve/fuel pressure regulator with this setup, isolated from the injectors and rail. If the pressure holds, how am I to release the pressure? Will the pressure naturally bleed off over time in a good fuel system? If so, what is the time frame?


Inline setup, will seal threads with plumbers tape

Fuel gauge with fuel line separators.

 

Fuel pressure should bleed off over time, though, it might take a while... Worst case, get a bowl, and a rag.

 

 

I have concluded that I will replace my fuel pump:

1. Separated the fuel line and installed the gauge, read 0 psi initially
2. Keyed on the truck, very little increase in psi to maybe 5 psi
3. Jumped the fuel pump relay, keyed on, no increase in psi
4. Jumped the ASD relay, keyed on, no increase in psi
5. With ASD relay jumped, fuel line disconnected, started and ran the the truck briefly with risidual fuel in fuel rail, then it died.
6. Installed ASD, connected fuel line, started and ran the truck briefly, then it died.

What say all of you experts? Now, to spend the money on an OEM pump or cheap out and take my chances with aftermarket? I have the 15 gallon fuel cell.


Beginning pressure

Presssure with key on

Control relay for fuel pump jumped

 

Get a denso, or delphi pump. Unless of course, you LIKE changing them....

 

I can think of nothing I look forward to less. Thanks for the tip. Those are cheaper than the Bosch!