Runs then dies after about 10-20 miles, sits for while starts again runs then dies

What does your codes tell you?

you have probably knocked somewires loose like cam sensor or crank sensor re check all your wiring near where you did all the work..

hello ther I belive it is your ecu very common

It sounds like your ignition coil is overheating. Once it cools down it will fire properly until it gets hot again. Replace the ignition coil and you should be all set.

fuel pump is a likely cause as it will run fine when cold and once it heats up it loses powers muffles backfires and dies.

Is fuel filter on backwards? This is common in fords cuz ppl run tank dry then switch tanks so all rust sticks to bottom of strainer some gets through. Start there look for arrow on side o filter point toward front

draw a small amount of fuel about 1 quart in sutable container and let sit then check for water.It will seperate in the sutable container

sounds like fuel pump getting weak.my 88 mustang did the same thing.if it starts and goes again after sitting a while ill bet thats the problem.

try checking your fuel tank for sediment it may be clogging the fuel pump and when it dies it falls away then when you start up again it gets sucked up

sounds to me like the fuel pump is bad, when it warms up it dies, try to check this by filling the tank and running a while, then run the van with a near empty tank and see how it does. A full tank of gas should keep the fuel pump cool as it is surrounded by the liquid. I had a similar problem. when my tank got to about a quarter full (3/4 empty) the van would shut off after a short distance, then after sitting for a while would start up again get me a little farther then shut off again. i ended up changiung the fuel pump cost me almost $300. if this simple test shows no results the you got electrical problems, check distributor, and surrounding cables. good luck. also check your fuses could be dirty!