im havin some problems with my swap, engine is in wired up connected and ready to run

but the engine turns over and sounds like its gonna start but it sputters some times but doesnt stay running

we have checked ecu, wiring, sensors, compretion, fuel, spark, timing

but i need some out side sources, anyone that knows ne thing about it let me know
thanx

email me at
CowBoyUp1086@hotmail.com