but the fuel pump worked fine before the swap so... it sounds like to me the fuel pressure regulator on the the new engine is bad. if it sticks open, the fuel will just flow right out of the regulator and fuel pressure will be so low the car will not start. i have had this happen to me before with junkyard engines. one way to tell is to pinch the return hose on the regulator with a pair of needle nose while someone cranks the car. if it starts, let go, or fuel pressure will get to high.