My sante fe wil sit and idle roughly why does it want to die when I give it gas?

What is your question?

My Santa Fe will hesitate to start when I first try to turn it over then it fires up and will continuously idle roughly when I try to give it gas it wants to die. Will rev up but as soon as I let go of pedal it starts to bog out but will not die unless I continue to give it gas. The weird thing about it is is that if I hold the pedal down in a certain spot it will continue to rev up but then bog out again as soon as I let it go.