phone got wet with salt water

The secret of saving any salt water electronic device, is to immediately, as it comes out of the salt water, submerge and flush it with fresh water over and over. Then remove it from the fresh water and immediately blow out all water with compressed air. Place the unit in a warm oven less than 90 F. Let it bake for several hours being careful not to overheat it. The alternative to this is to use a warm (not hot) hair drier, and a lot of time. Don't become impatient and overheat the unit. When you are completely certain that it is dry, inside and out, replace the battery and start it up.

Speed in getting it into freshwater is the most important aspect. Do not allow any salt water to dry in the unit. Also I forgot to mention remove the battery as soon as possible preferably as it comes out of the fresh water or before.

It's most likely the phone is beyond repair by now. Salt water is incredibly corrosive and if enough got in to short circuit the battery, some damage has occured. Salt water damage can SOMETIMES be fixed but rarely after letting it sit and corrode for two weeks. You might as well pull it apart and have a look.

I'm with 'beyond repair' above me. That said if your time and efforts are free to you, you have only the cost of parts to worry about. I would recommend a limited approach, as the salt walter tells me 'reliable' may not be in it's future if it works at all. My definition of limited approach- try the battery. If that does not work, STOP. One could go down the rabbit hole on this one, buying part after part, until you were better off just getting a cheap 3GS.

This might be kind of late, but try cleaning the phone connector with some rubbing alcohol and hydrogen peroxide and a q-tip. You can cut the middle of the q-tip at an angle to create a pick to get gunk out of the connector and use the peroxide and rubbing alcohol to clean off the leads (metal connectors). I had to flatten the q-tip end (I used pliers) so it would fit inside the connector on the phone. I was amazed with the sharp end how much stuff I got out (make sure the connector/wire goes in all the way). Then when I put peroxide in, it foamed and then I rinsed it out with rubbing alcohol and wiped more dirt off the leads with the soft end of the q-tip. I was able to charge my phone once, but had to repeat the process to get it to charge again.