Can the bible become an idol? Absolutely, if you believe you can just read and study this COLLECTION of ancient books - not one book, just a reminder, and then it will transform you and all your problems magically go away, then the bible has become an idol. Take Philip's evangelization to the Ethiopian eunuch for instance -
So Philip ran to him, and heard him reading the prophet Isaiah (53:7), and said, "do you understand what you are reading?" And he said, "How can I, unless someone guides me?" And he asked Philip to come up and sit with him. - Acts 8:30-31
The same applies to us. The Scripture is sufficient, but you yourself are not. We all need teachers and peers to guide us in our spiritual journey. This is why I believe that testimonies, evidence and experience that validate the bible is what really transform you, especially authentic experience that gets into your muscle memory.