Jelaine3, I've discovered in troubleshooting fuel pump problems of my own (96 Silverado Pickup) recently that there's several possibilities that can make that engine crank over but not start. The following 2 items are not the only things that can affect your son's problem, but they need verifying. The fuel pump receives electrical power thru a parallel circuit; it begins when the key is turned to the run position by sending current thru a relay in the "underhood relay center". The relays (about 4 or 5 depending on how the vehicle is equipped) are labelled inside the top cover of the relay box. They simply plug in and pull out as necessary to test or replace. The fuel pump relay is a 5-pin relay, and powers the fuel pump during the start process. As soon as the engine does fire and run, oil pressure should build up almost instantly. When it reaches at least 4 psi, the oil pressure switch becomes the circuit that provides electrical power to the fuel pump, and supposedly the fuel pump relay goes to sleep, un-needed during the normal run. (I'm not 100% convinced the relay does this, but that's a whole 'nother story!) The oil pressure switch is considered the safety switch in the event of a crash. An impact that is sufficient to stop the engine also stops the oil pressure when the engine quits. The electrical power is removed from the fuel pump and fuel is not being pumped all over a hot, possibly sparking engine. Verify that the relay is providing electrical power to the fuel pump when the key switch is turned to the run (not crank) position. It should run the pump audibly for about 2 or 3 seconds. I've had old and new fuel pumps in my truck, and I've been able to hear them all if there was not a huge amount of ambient noise. The radio on at normal volume is enough to hide the pump noise. Verify that the oil pressure sending unit is plugged in properly. It's right down under/behind the distributor. It would be very easy to have disconnected that while working on the distributor, and missed reconnecting it.