In fact, a healthy vagina SHOULD BE slightly acidic. Fungal infections can result from an imbalance in the normal organisms raising the pH a bit. The smell and taste are only partially related to pH, though, as a woman can have sebaceous (basically sweat) gland secretions, and a natural odour that can be like a fingerprint. Unique to each woman if the partner or self is sensitive enough to detect the nuanced differences. My rule of thumb is that my smell and taste should be "me", but an "OFF" smell signals a change. I know its kinds confusing, but look for any symptoms or discomfort. Not a bad idea to be checked out regularly in any case.
You should go get checked out at a free clinic. It may be a bacterial infection, or yeast infection. They can easily prescribe creams, or pills to correct this.
Good luck!