Car dies at stops only
i have a Chevy Cavalier 2002, 2.2 automatic/gas
i have done a tune up on it, changed out spark plugs, oil filter, air filter, changed out engine oil, even flushed transmission oil on it, seems to run pretty good, except at stop light, or whenever i need to make a stop. Otherwise it works fine, i just got the car , so dont know too much of it, but it was running fine when i got it.
please help! any suggestions? mechanics in this aren't trustworthy and they just keep draining money and dont do they job