02 Express low idle

Had trouble starting the van after it sat for a while. They put a used computer in it which was set up by the dealer but later they found out that the distributor cap was getting fuzzy because the filters in the distributor were clogged and the moisture had no way to escape. They took the filters out and the van starts fine but now it idles so low that sometimes it stops at stop signs and when I take my foot off of the gas to corner. That's pretty dangerous because I lose brakes and power steering. When it does idle, there isn't any missing, it's just low and there's no lagging or missing when I accelerate. I'm wondering if the CPI is bad? Is there any way to increase the idle because it seems if I could increase the rpm's, it'd work just fine. Thanks for your help.