kills when wet

For mothers day the wife wanted to go on a bike ride, she took her mtn bikeiI took my Polaris Figured it has been raining all night and morning. Found a few puddles in the road and went through them, my 1998 Polaris sportsman 500 sputtered when wet. But ddidn’t die. It started to rain more and it seemed to want to die when it got wet. After a few times it would die, but always start back up. My question is what the $%&#& happens. I take this elk huntingin rain and snow so iI’d hate to be stranded because my ATVgets wet. What should I look for? When it starts up I can’t go too fast because it Biggs down and dies.