How to avoid accents beeing displayed as question marks on NodeJS

I'm getting a file via fs.readFile and the output shows these characters:

á (and any letter with accent), ¿, etc.

As question marks "?".

I guess it's an encoding problem, since I'm using UTF8, how can I fix this?

if you are showing your content in HTML

set <meta http-equiv="content-type" content="text/html; charset=utf-8" />