I have a 2007 ford mustang, my brother took the motor out to replace both timing chains, after he set it in time and put the motor back in, the car just turns over and won't start, even when u hook it

I have the same problem. I got a 2005 Mustang with the 4.0 from a guy the overheated it. I had the heads repaired, and replace all of the chains. I put the engine back in the car, and made sure that the timing was dead on before putting it in. I turn the engine over and it started for about 1 to 2 seconds, and died. I tried to start it again and it will not start. It acts like it wants to but will not. I took the injectors out and checked them, and they are working fine, and the spray pattern looks good on all of them. The spark plugs are new, and only two or three of them show that they were firing. I checked for spark and it is very little coming from the coil/distributor pack. Fuel is good but very little spark. I have replaced the Crank Shaft Position Sensor, and no luck. No codes are in the computer, and the Anti Theft system is off. Any idea on where to go next?