my four-wheeler dies when i hit water but it startes right back up what is wrong with it?

Question

it is a 2003 400 2x4 bigbear

Answer 1

Maybe the water is shorting out the spark plug.
Remove the spark plug cap and inspect the rubber seal between the cap and wire.
They're cheap enough, try a new spark plug cap.
It could be any # of electrical problems.
Ignition switch.
Kill switch.
Bare wire to the coil.
Check all connectors and wires.
If it happens every time you go through water -
One at a time, seal up a connector or switch water tight with a plastic bag and electrical tape.