Well, if you have spark and the van still wont start, then that means no fuel. You beed to get the fuel pressure checked. The fuel pump may have gone bad.
Or you can lay under the van and have somone turn the key to ON, not crank, ans listen for the pump to hum in the gas tank for 2-3 seconds. If not, pound on the bottom of the tank. Sometimes this will free up a stuck pump for a little while. If you do hear the hum, then you need to check for proper pressure. Just because it runs does not mean the pressure is high enough.
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