Fuel and Spark, but no start

I've checked the timing and it's dead on. Fuel pressure is good, getting injector pulse, and can smell it on the plugs. Distributor is brand new, and it's giving a strong spark. Main Relay is new too. I've tried about everything and still can't get it to start. The ecu will do one quick flash and that's it. Could the ecu be the problem or does anybody have any other suggestions? Thanks.