idle question on 98

Quick question..

A friend of mine is having trouble with her 98 cavalier w/ 70k (it is an auto). When she comes to a stop light or stop sign the cavalier starts to idle very low like it is going to die. Sometimes it does die at a stop. When she turns on the A/C and then stops it always dies.

Waht could be the problem? Fuel filter what just replaced and still has the same problem.

Thanks
:confused:

my first guess (since it's not the fuel filter) would be the fuel injector or fuel rail. put some STP fuel injector cleaner in your gas, should clear it up. but i don't understand wut the a/c would have to do w/ it, then again i may be wrong....