ram van loses spark after short drive

[roofcock]

94 250 w/360 engine. i can start the van in the morning and leave, drive 8-10 miles to gas station turn it off, fill the tank. then no start. wait a period of time and it starts. when this happend for the 3rd or 4th time i checked the coil and it had no spark. a short sit and it came back (spark). sometimes if i dont cut it off or if i stay where i am going i can drive all day no problems. well i was dealing with it. the problem is it is getting worse. the other day i am on I-95 at 80 mph and it cuts off, pull over battery dead. get new battery fires right up, drive 15 miles cut it off. wait about 10 secs turn key fires right up. walk in store get coffee, come back no start. sit ther 20 mins fires right up and i drive off. i realize something gets hot and breaks down, cools off and comes back but... does anyone have an idea as to what it could be. sometimes it wont do it for a couple days and sometimes everyday. any and all replies will be much appreciated. thanks

[alloro]

Since you're not getting spark, you'll need to see if there is power on the primary coil wires during these times of trouble. If there's power then the coil is bad. If there's no power it could be anything including a loose connection, the ASD relay, a bad battery cable, a bad pickup coil, a bad crank sensor, or a bad PCM.

[roofcock]

the coil is new. that is what ithought the problem was in the begining. is the asd the auto shutdown which kills the fuel also. i can turn the key and hear the fuel pump turn on but have no spark, so if it is that it would have to be killing only the spark not the fuel... is that possible

[alloro]

In 94 there was a separate ASD relay and a separate fuel pump relay. Although they are both combined together as one unit located around the bottom of the master cylinder.

[roofcock]

is there a way to test these relays with an ohm tester, volter tester, any tester

[alloro]

Sure, you can apply 12v power to the relay coil and listen for clicking. Once you've confirmed that it is clicking, use an ohmmeter across the relay's contacts to see if you get continuity when the relay is energized.