I have a 1984 crossfire injection, and I have replaced the water pump, thermostat, I took the radiator out and cleaned it from over the years of build up, and changed all the fluids and my vette is still over heating, but when Im driving down the highway its cool, but when I come to a stop light it gets hot, only at a stop sign or red light, what could be the problem??

 

Is your fan working? Usual sign, overheating in traffic and cools down on highway because of airflow across the radiator.