2002 Grand Prix Accelerator Sticking

Our 2002 Grand Prix had the acclerator stick on about 80% full throttle yesterday while driving down the road. Had to jump out of the car and pop the hood and manually release the throttle.
The garage took apart throttle body etc and could not find any problems. Has anyone else heard of this problem and any suggestions? Thanks

If you're still driving the car, just remember to stomp the accelerator if it happens. I would hate to see anyone get hurt, and a lot of people think that sounds stupid, that you should hit the brake. A lot of times if you'll stomp the accelerator, it'll unstick it. As for why it's sticking, did you make sure nothing was obstructing the pedal?