My vagina has a sour citrusy taste. what could be the reasons.

Maybe normal: This may be entirely normal. The vagina is normally acidic and a somewhat sour taste is to be expected. At age 16, your sexual maturation may still be underway as your vagina and genital tract settle into what is normal for you. But if this is a major change, or if you have other symptoms like irritation, itching, or increased discharge, or if you just want to be sure, see a doctor or clinic.