ive gone through a new starter,, ignition switch battery fuel pump, a resistor, can figure it out. it has fuel and spark. but it only fires and wont run. HELP

 

I had the same problem with my 85 and it was a grounding issue. We took a ground wire from the batterey ran it to the front of the truck and grounded it to the metal and it worked for us.

 

(1) loose or damaged wiring in the ignition system.
(2) intake manifold vacuum leaks make sure all mounting bolts/nuts are tight and all vacuum hoses connected to the manifold are attached properly and in good condition.
(3) faulty idle control system.
(4) faulty emissions or engine control systems.