Turn your car while in the water
Well it is possible and yet simple. First, go get a car ( not a bike or motorcycle ) then speed going through the water but do not exit the car. Keep speeding and the car should float. Press your [handbrake] key + left or right d-pad. You should turn around but the car will start to sink and reducing your oxygen. Hope this helps ^_^
More tricks, tips and cheats for this game are right here - Grand Theft Auto: San Andreas cheats
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