In the Scholar module, when "Render Google Scholar Search link" is enabled and the default settings are used, the rendered search is an empty query (q="") for objects that have no DOI, despite the setting to use the title field when no DOI exists. This applies only to objects that were ingested manually (via the form).
The ingest form creates an empty <identifier type="doi"/> line in the MODS XML, which Scholar incorrectly interprets as a DOI being present. If the MODS XML is downloaded, the line deleted, and replaced, the query correctly includes the title field.
This empty <identifier type="doi"/> is generated by the default citation form included with Scholar, as well as custom forms that I created.
Objects with no DOI ingested via batch ingest, which did not include the empty <identifier> field, render the GS query properly - see http://arcabc.ca/islandora/object/unbc%3A6116 for example.
This issue was tested and confirmed on our production repository (at arcabc.ca) and on Vagrant (see attached screenshot).