diff --git a/homeassistant/components/sensor/bitcoin.py b/homeassistant/components/sensor/bitcoin.py
index 31c6c1809b3ba6..0a3f568a383c44 100644
--- a/homeassistant/components/sensor/bitcoin.py
+++ b/homeassistant/components/sensor/bitcoin.py
@@ -14,6 +14,7 @@
     CONF_DISPLAY_OPTIONS, ATTR_ATTRIBUTION, CONF_CURRENCY)
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import Entity
+from homeassistant.util import Throttle
 
 REQUIREMENTS = ['blockchain==1.4.0']
 
@@ -178,6 +179,7 @@ def __init__(self):
         self.stats = None
         self.ticker = None
 
+    @Throttle(SCAN_INTERVAL - timedelta(seconds=5))
     def update(self):
         """Get the latest data from blockchain.info."""
         from blockchain import statistics, exchangerates
diff --git a/homeassistant/helpers/entity_component.py b/homeassistant/helpers/entity_component.py
index 2833010789ef5b..46c45a6fdec278 100644
--- a/homeassistant/helpers/entity_component.py
+++ b/homeassistant/helpers/entity_component.py
@@ -374,6 +374,16 @@ def async_add_entities(self, new_entities, update_before_add=False):
         if not new_entities:
             return
 
+        hass = self.component.hass
+
+        # If the entities are not async, update them in sequence to avoid
+        # race conditions when component uses throttle.
+        if update_before_add and any(not hasattr(entity, 'async_update')
+                                     for entity in new_entities):
+            for entity in new_entities:
+                yield from hass.async_add_job(entity.update)
+            update_before_add = False
+
         @asyncio.coroutine
         def async_process_entity(new_entity):
             """Add entities to StateMachine."""
@@ -385,7 +395,7 @@ def async_process_entity(new_entity):
 
         tasks = [async_process_entity(entity) for entity in new_entities]
 
-        yield from asyncio.wait(tasks, loop=self.component.hass.loop)
+        yield from asyncio.wait(tasks, loop=hass.loop)
         self.component.async_update_group()
 
         if self._async_unsub_polling is not None or \
@@ -394,7 +404,7 @@ def async_process_entity(new_entity):
             return
 
         self._async_unsub_polling = async_track_time_interval(
-            self.component.hass, self._update_entity_states, self.scan_interval
+            hass, self._update_entity_states, self.scan_interval
         )
 
     @asyncio.coroutine