96 gt sputtering and backfiring

Under low rpm, the car sputters badly and what sounds like backfiring as well. Once into the higher rpm's it clears up a bit, but still doesent have the power that it should.

Plugs and wire's were done but with no help. Any idea's?
 
check leads, plugs, injectors, injector plugs.

make sure all are ok, make sure all your leads are properly seated, check ur plugs and make sure none of them are covered in fuel ( indicating injector fine, plug/lead not so much)

Si