my 91 ford van 5.8l trouble is it recently devloped what seem to be open firing in both intake and exhaust it seems in all or no specific cylinder cant seem to locate problem did all the usual pl,wres,cap rotor, tps,egr,fuel pressure at 40 no drop didnot think it was timming chain but i guessit could be but will it run if it did only 69000 original miles good shape . please help

 

Let's see if we can eliminate some possibilities.
From what you describe, I would start with the distributor area.
First- did you have this problem before you changed the cap, wires etc.?
If you did, this is what I would check.
Mark the distributor position on the dist housing and the engine block so when you reinstall it ,it will go back into the same position.
It is always best to get the engine timing mark on the crank pulley lined up with the pointer on #1 cylinder. Remove the dist cap and the rotor should be pointing to the #1 spark plug wire on the dist cap and that wire should go to the front most spark plug on the passenger side of the engine.
This should tell you 2 things.
1. You have the first plug wire in the firing order in the right place.
2. The pin on the dist drive gear is OK.
Before I give you too much to do , how about you let us know if these things check out OK ?