Can't connect to Cloud SQL when deployed on App Engine

Hello, I have billing enabled for Cloud SQL and using App Engine for free.  

Connecting to the database works fine developing locally, but when I deploy to app engine and run it in production I don't get any results back.  

The Admin Logs state "API serving not allowed for this application".  There are no stack traces or anything in the logs.  I have authorized the app engine application in the Cloud SQL instance.

Does this mean I need to enable billing for App Engine?

I saw an answer about applying for Endpoints access but I don't think I'm using Endpoints.