98 venture stalls when at lights (damp)

my venture stalls at lights and durring idle when it's damp/raining. My engine light will flicker and I bog alot at the lights. I had the same problem with an old 90 tempest, just need a fix. Don;t feel like getting riped off at the mechanics...thanks in adavance.

if no-one knows exactly how to fix it, is there a temporary fix....it's getting trading in soon and I need to drive it around quite a bit/