Engine shuts off at low idle

My car keeps shutting off at low rpm's either stopped and idling or just coming to a stop at slow speed. Tune up less than a year ago, new plugs and all that fun stuff. I replaced the fuel pump when the problems first started occurring. At first the car when pressing down on the gas would not go past 65 mph on the interstate and it seemed to be starving for fuel when it reached around 3000 rpm's. Even in park as I try to rev up the rpm's pass 3000 or so it would sputter and not go any higher. It did stall a few times before I installed the fuel pump. After the new fuel pimp it accelerates like new never have a problem with sputtering, but now at idle and stopped at a light or coasting at low speeds (10 mph) it stalls. Replaced battery and connectors, had the idle adjusted from 400 to 600 rpm's. No error codes suggestion cam shaft sensor. No check engine light comes on. Read about computer needs to reset itself but how? Does not have factory stereo. Out of ideas and the rest of my hair I would like to keep. Thanks.