1991 Jeep Wrangler stalls when approaching a stop...?

or when I am trying to turn. I just bought the car a month ago used and took it to a Jeep dealer who was extremely impressed with the condition it is in and said it runs great. Well now I have had it for a month and every time I approach a stop sign, red light or trying to turn on a street at low speeds the car stalls. It is a manual transmission, 4.0L engine. I lose the power steering too when it stalls, obviously, and I almost got into a lot of accidents. Does anyone know why this is doing thi? Any help please, also I am not a mechanic so please used laymans terms. Thanks.