I've never heard of it.
I'm just thinking if there was a way as easy as that, you would think word of mouth would have gotten around.
I would say no, but I do not know for sure, as I've never heard of this.
Hopefully someone else out here can shed some light.
Not really a myth. Soaking an area in which you suspect to be a HPV wart will cause the wart to turn whitish. If it is not a wart, it will not turn white. However, soaking your penis in vinegar will not prove whether you have HPV or not. There are many types of HPV which are asymptomatic and the type that causes warts may be dormant or at least not forming warts yet.