92goldsc

Can someone please help... my sc was working fine 2 weeks ago...and one day after work I was on the high way got up to traffic at about 20mph the engine stalls out..try to start no start...put it in nuetural held my foot on the gas ...started right up...now every once in a while it does the same thing ...drives fine and then when it want it stalls out when I slow down anytime under 20mph...I used lucas fuel injector cleaners and not really helping much...any one have a idea of what it can be causing this problem ?