What would cause a Mazda B3000 to not start after it has been sitting The engine will turn over fine but it will not fire?

I have a 1994 B3000 that started doing that several years back. It was a relay that was located within a black box on the drivers side of the engine (I believe there are 3 relays in the box). I found that one of the relays was sticking. When lightly 'tapped' on it would release and the engine would start. After replacing it, the problem went away. Note Did they have the "Fuel Cutoff Switch" in those years of pickups? Typically, it's designed to remove power from the fuel system in the case of an imact or jarring. Check to see if it was somehow popped, and just push the button back in if you have one. Should be under the dash, right above or at the top of the carpet/floor mat passenger side. Little box with a single plug and a red button at the top typically. It may also be the ignition module. I had the same problem with my '94 B-3000. If it sometimes dies on you while driving it probably is the same thing. After replacing it the problem went away.The module is easy to replace. It is located on tn the front of the vehicle , drivers' side next to the radiator. Also tapping it several times may get you by until it can be replaced.
good Luck.