1993 cavalier rough running problem

I have a 1993 cavaleir 2.2L The problem is it will be running fine till you get ready to stop and you can feel a change in the way it is idleing . It startes to vibrate and  shake and wants to stall. It will start back up again, but when it is put into drive or reverse it quits running. Some people have told me it could be the electronic ignition control module.Is there any  member that might have some insight as to what the problem could be ?

I had a similar issue with my '90 cav, but only when it was raining or damp out

is this all the time or only when there's high humidity?