1991 Chrysler Imperial

1991 Chrysler Imperial Two Wheel Drive Automatic

The car hadn't been used in a year or so. After driving it for about 45 minutes to an hour I felt a click or sort of jolt with some minor shaking towards the front bottom of the car. Before this when I would press the gas and let go the car would cruise for a while and slow down slowly. After this I had to press hard on the gas constantly and when I remove my foot from the gas the car slows to a stop almost instantly. What caused this?
-Dani