1998 Escort not accelerating

Car is not accelerating from a stop. It is slow only at the start, but once it starts running. no problem. I think it might be the fuel filter. Car had and engine swap in June and the computer module was swapped. Does this with A/C off or on. Any help.
Thanks

Check to make sure your spark plug wires have a tight connection. If they are, check the plugs themselves. It sounds as if you might be running on 3 cylinders rather than all four.