starts.... goes dead

I just replaced the head gaskets on my 93 3.8 liter, and put everything back the way it came off. I went to start it and it starts, runs about 2 seconds, then goes dead.
Any ideas? I checked to make sure the plug wires are in the correct place.

I have heard of this happening and one of the reasons/solutions was that either the fuel pump was failing or in another case the fuel filter was nearly clogged.
Try doing a volume test on the fuel system.
Another possibility is a fault in the charging system, such as a nearly dead battery or failed alternator. The last item is that some security systems when faulty or detecting a fault will not allow the car to continue to run.

Thanks for the input. At lease this will give me somewhere to start...