Cadillac Repair: Loose throttle at high speeds., gas tank, fuel tank

Question
I have a '94 Deville 4.9L. I am unable to drive at higher speeds (50+) for any period of time because I loose throttle. When I press the pedal, I get no response. I have to turn off the car and let it sit for 5+ min. to have the ability to go anywhere. I have no problems with the throttle driving in town. Initially I was able to drive for excess of an hour without have a problem but gradually the span of time shortened and now I can't even got 5 miles without loosing throttle. I changed the fuel filter which I though helped. There was flow blockage when I emptied the filter. I was able to drive for a longer period for the first trip but then the next time I tried to drive on the highway and it was worse. I can't figure out what's wrong. I need some help.

Answer
Remove the new filter and dump out the contents and see if there is any foreign debris coming out of the filter. If there IS, There is another filter located at the bottom of the fuel pump in the gas tank of which you will have to remove the gas tank and empty out all the gas, clean the fuel tank and replace the filter on the bottom of the pump.

What is most likely happening is that there is foreign debris within the fuel tank and as you drive it, the pump is sucking the debris onto the filter in the gas tank and stopping the flow of gas. Once you shut OFF the car the foreign debris drops off of the filter until you restart the car and the debris recollects on the filter restricting the gas flow.