Wife's Daily Driver need help ASAP please

[heavy_dman]

Okay, for some reason my wifes 94 explorer dies after getting warm, I get no power to the fuel pump, the relay and the 20amp fuse under the hood are all good, just put in new inertia switch from ford, and am about to go crazy. Now the really crazy part is, if you let it sit for a few hours and cool off, you then can hear the pump again, and it'll crank up and run fine until it reaches running temp,(around 190) then as soon as you stop the car it'll sputter out again, and the fuel pump won't come on, until it cools back down. Has me stumped. Any suggestions.
Additional Info:
Fuel pump and wiring harness are 6 months old
new FORD Relay
new MAF
New Inertia switch
Also, when I replaced the Inertia switch, the wire leads on the old one were a little burnt, but the harness looked good, replaced it anyway though.

 

[colintrax]

The wires were burnt??? I'd say that's a short, although that should also have started a fire considering it's touching carpet.
Not sure what changes, I guess the fuel pump runs at a lower psi once warm (are you getting a lean code?) since the "choke" is off. Could be that it's not getting enough power to pump once warm but it's getting enough when cold because the "choke" is on. Bout my only guess :scratch:

 

[heavy_dman]

not so much as burnt, just a little black,and not wires the connector leads where the harness plugs in. couldn't run codes, broke down on her 20 miles from home, gonna try to get it home tomorrow, it should run long enough to get it home, then going to try to run codes, just hoping for some advice because I have a really busy intersection no matter which way I take home so it has a perfect opportunity to die before i get home.

 

[colintrax]

I would guess black is still burnt. I'm not a huge electrical person though so maybe someone else can help. Good luck on getting it fixed.
Do you have a Haynes or chitin's manuel? If so, start testing ohm's and voltage across the fuel system and compare to the manuel

 

[TedJ]

When you try to restart it after it dies, does the check engine light come on with the key on before you try to crank it indicating power to the EEC?

The EEC relay needs to work too. If it's not powering on the EEC, then there is no trigger for the fuel pump relay either.

If that's working, then check for voltages at the relay socket when its supposed to be triggering. You can take some thin wire and slip it in the relay socket before plugging in the relay to give you a test output. There should be battery voltage on the 87 terminal when the relay is triggered (pump on).

 

[Tony H]

I'm with TEDJ.. The fuel pump relay was changed but the EEC is working just as hard. That relay ( or socket for teh relay) may be heating up and dropping off.

 

[heavy_dman]

replaced both relay's with new ones from dealer

 

[heavy_dman]

pulled pcm, to check for bad capacitors, they look fine but its hard to tell with all the clear coating on everything, not sure if they're bulging or if its just the gel. but the whole board looks pristine so its back to the drawing board

 

[heavy_dman]

ran koeo test came back KOEO 335, and CM 214, but neither really explain why after several miles my fuel pump stops getting power.