only after a long drive

[Dav]

95 2.3 auto
the truck dies after going for much more than an hour continuously. just cuts out like i'm out of gas. sit on the roadside for a while, anywhere from 5 minutes to an hour, and it starts right back up and goes. after the initial problem, it might go for 30 seconds or might go on the rest of the day.
it is not running hot.i have swapped the relays, just the 3 square ones, but that doesn't help
i can't even start replacing stuff in hopes of getting it right because i have no idea of where to start.
any hints?

 

[Dangerrangers]

Check the fuel pump pressure when it won't start or stay running. Hopefully RonD will jump in here soon ,he will have better info than I .

 

[Mark_88]

Could be the fuel pump is on the way out. Could also be a wonky inertia switch that doesn't quite kick out completely.

How long has it been doing this?

 

[Dav]

it's been doing it for probably a year. i dont drive over an hour very often. the fuel pump was last changed about 4 years ago with, admittedly, the cheapest one that the local parts store had
what confuses me about this is that the truck does fine until i have to slow down, like going from freeway speeds to taking an exit and hitting the city streets. that's when it starts screwing up. it definitely acts like it did when i last changed the pump but why only after i slow down? can it be something not in the fuel system?

 

[tomw]

Next time the problem occurs, try cycling the key from OFF to ON, and pause, listen for the fuel pump to run for a few seconds. If it does, then you likely have an ignition problem. If the fuel pump does not run, then you have to investigate the power circuit to the pump. The rollover/inertia switch mounted above the top edge of the carpet, passenger side, under the glovebox, could be flaky. Press the button on top a few times to jiggle the ball bearing resting on the contacts. Try the key again, listening.
tom