2003 Cavalier Dies at Deceleration

Please help! I have been having trouble with this issue for about 3 months now. Here's what is happening. My cavalier dies when coming to a stop. The problem started out very gradually but has gotten much worse over the past couple of weeks. My younger sister has the same make and model of cavalier and hers does the same thing. We have had our vehicles in for repair at a chevrolet dealership a total of 5 times and they can't seem to figure out what is going on. At times, the car doesn't die, but the RPM's drop to about 200 RPM and it takes a few seconds for it to jump back up to idle speed of about 800 rpm. Does anyone have any ideas or suggestions? The only thing the location has done so far is clean the fuel injectors. Thanks!

lemon law... check it out

IAC valve needs replacing.