hey there ya'll.

I hope you can help me.
before my problem let me give my trucks info

1998 f150 supercab
brand new engine put about 10000 miles on it so far
new tranny about 15K on it so far


ok yesterday we had alot of street flooding.
i drove through alot of water about mid tire high
when i came out of the water i had a very strong shutter and the check engine light came on.
i figures after i drove a bit it would dry out a bit and then go away.

well it has not . the code is a p0303 which is missfire on #3. my question is NOW WHAT.

what could i have done ?? did the water burn up a plug or wire?? i'm not sure where to start.
it has been two day so i would assume its dry by now.
any info would be great