no third gear problem--help

[stanger66]

now with the shifter I put it in the first drive position I come to
I have even tried putting in the small dot and doesnt shift at all.
Now I was wondering there is a cable that links up to the gas pedal and it has slack in it would that have anything to do with. but it goes from the gas pedal linkage to the side of the trans. should I take the slack out of it. My shifter goes p-n-r-big dot-small green dot-L.

ross