diff -u b/core/modules/field/field.install b/core/modules/field/field.install
--- b/core/modules/field/field.install
+++ b/core/modules/field/field.install
@@ -391,7 +391,7 @@
     }
 
     // Store with the old field_id so that we can map the instance.
-    $field_uuids[$field['field_name']] = $config['uuid'];
+    $field_uuids[$field['id']] = $config['uuid'];
   }
 
   $instances = db_query("SELECT * FROM {field_config_instance}")->fetchAll(PDO::FETCH_ASSOC);
@@ -408,8 +408,8 @@
       'label' => $instance['data']['label'],
       'description' => $instance['data']['description'],
       'required' => $instance['data']['required'],
-      'default_value' => $instance['data']['default_value'],
-      'default_value_function' => $instance['data']['default_value_function'],
+      'default_value' => isset($instance['data']['default_value']) ? $instance['data']['default_value'] : array(),
+      'default_value_function' => isset($instance['data']['default_value_function']) ? $instance['data']['default_value_function'] : '',
       'settings' => $instance['data']['settings'],
       'widget' => $instance['data']['widget'],
       'status' => 1,
@@ -418,7 +418,7 @@
 
     if (!$instance['deleted']) {
       config('field.instance.' . $config['id'])
-        ->setData($instance)
+        ->setData($config)
         ->save();
       $manifest_ids['instances'][] = $config['id'];
     }