Well, when my truck is cold and i want to like go i give it gas and i hear like water flowing thrue something or another near the passanger side it sounds rlly weird just like water flowing anyone know wat this is?

 

Sounds like your evaporator housing drain is plugged up and the housing has got water in it. If it gets bad enough it will run out of the heater vent when you go around a corner. At least it's an easy fix...look under the hood under the a/c drier where the drain comes thru the firewall and make sure it isn't stopped up.

 

I'd say you have air trapped in the heater core and what your hearing is the air being pushed around. make sure your rad is topped off and go drive.