diff --git a/src/Plugin/search_api/processor/RenderedItem.php b/src/Plugin/search_api/processor/RenderedItem.php
index 5f29a9e..635f6d2 100644
--- a/src/Plugin/search_api/processor/RenderedItem.php
+++ b/src/Plugin/search_api/processor/RenderedItem.php
@@ -200,6 +200,9 @@ class RenderedItem extends ProcessorPluginBase {
     // @todo Why not just use \Drupal\Core\Session\UserSession directly here?
     $this->currentUser->setAccount(new UserSession(array('roles' => $this->configuration['roles'])));
 
+    // Count of items that don't have a view mode.
+    $empty_view_modes = 0;
+
     // Annoyingly, this doc comment is needed for PHPStorm. See
     // http://youtrack.jetbrains.com/issue/WI-23586
     /** @var \Drupal\search_api\Item\ItemInterface $item */
@@ -215,7 +218,8 @@ class RenderedItem extends ProcessorPluginBase {
       $datasource = $item->getDatasource();
       $bundle = $datasource->getItemBundle($item->getOriginalObject());
       if (empty($this->configuration['view_mode'][$datasource_id][$bundle])) {
-        $view_mode = 'default';
+        $empty_view_modes++;
+        continue;
       }
       else {
         $view_mode = (string) $this->configuration['view_mode'][$datasource_id][$bundle];
@@ -225,6 +229,10 @@ class RenderedItem extends ProcessorPluginBase {
       $field->addValue($this->getRenderer()->renderPlain($build));
     }
 
+    if ($empty_view_modes > 0) {
+      \Drupal::logger('search_api')->warning('Items without a view mode: ' . $empty_view_modes);
+    }
+
     // Restore the original user.
     $this->currentUser->setAccount($original_user);
   }