not shifting out of park

my grandma owns a 1999 intrepid and many times now she has been unable to shift it out of park. Even I have tired, with no luck. Sometimes it works, sometimes it doesnt. You can step on the brake and pull the little trigger thing thats supposed to make it slide, but it doesnt budge. My father got in it once and pulled with a lot of force, and managed to get it going, but now it has stopped working again. We opened the hood and tried to look for the shift linkage to see if something was jamming it, but couldnt find it. anyways. what could be causing this? Sometimes it shifts fine, other times it doesnt shift at all.

Needs a shift cable and it is a dealer part only,cannot get it from any auto parts stores.Sounds like the shift cable is froze up.

May wanna check for a recall on that one.I think I might remember that I forgot that I should remember that one.

There was a recall on it,not on the shift cable.It was the shifter base that was recalled.It is the shift cable,froze up and I have heard of this happening once,would not go out of park in a Chysler LHS.

checked your shift interlock solenoid for power, ground and proper adjustment, when you step on your brake you should hear a slight click sound from near your steering coulmn, check the fuse and linkage