1999 Other Oldsmobile Models Sputtering in the Rain

1999 Other Oldsmobile Models Automatic

HI, I have 99' Oldsmobile Silhoutte. It seems every time it rains the car starts to sputter after driving it for a while maybe a mile or so. I give the car gas to go and it starts to sputter I can't get it past about 10 or 15 mph, so I'm basically costing. I have had the gas filter chanaged, a complete tune-up including an oil change, I have put dry gas in, I have even had it checked on the computer and nothing comes up. I have had all this done in the last 3 months. Can you help. With much hope Jailyn