CAR DIES WHEN DRIVING IN THE RAIN

2002 FORD TAURUS, 3.0 6CYL 56,877 MILES; I Had trouble with the car bucking when raining, then it would stall, start up, but stall again.1st cleaned fuel inj. And changed gas filter. When it rained again, it did the same thing. Ford DLR. Changed MASS AIR FLOW SENSOR. Ran good for a month, then started to miss fire. Did a tune-up, ran great until it rained. I was able to drive about 15 miles or so, when car just died. AAA had to jump start, but later that evening it would start but died when I would put in drive. Next day mechanic starts it right up, drives around the block and it justs rides great. Runs great as long as it dosn't rain. His intends to take it next time it rains and drive it for half an hour to see if he hears something to help him out. Can you give me some help. I'm afraid to get caught driving in the rain? Clare