car still idles but does not accelerate while in motion

While driving in the dark (only) my traction light comes on. During this time, while I am driving, the car fails to accelerate. It will lose all momentum. The car never shuts off. I have to remove my foot from the gas and reapply it, for the car to correct itself. Very scary. I drive on the highway everyday to and from work. sometimes it does it repeatedly, giving my car a "hopping" feeling. It does not do it every morning but at least 3-5 times a week. Some days I am worried I will not make it to work or worse get hit from losing speed.