21 YR OLD COLLEGE STUDENT IN NEED OF HELP! Vehicle just stopped running: replaced fuel pump and filters, crank position indicator, and ignition relay. Have 42 psi fuel press to the rail, engine will fire on starting fluid then die after burn off. Unplugged injector electrical lead and placed tail bulb in socket to test for electrical power to injectors and had negative result. Therefore I know engine should run but need to know what is preventing electrical power to get to the injectors. Have been told either a "short" or the computer. Also been told since it is a 4.0 that is a Mazda engine and also that about any 91-94 ranger, areostar, explorer, or mazda b-4000 computer "should" be compatible. Obtained a 94 explorer computer and tested with negative results. HELP!