diff --git a/ceilometer/tests/ipmi/platform/test_intel_node_manager.py b/ceilometer/tests/ipmi/platform/test_intel_node_manager.py
index bc5513e71..a7cb03f29 100644
--- a/ceilometer/tests/ipmi/platform/test_intel_node_manager.py
+++ b/ceilometer/tests/ipmi/platform/test_intel_node_manager.py
@@ -29,6 +29,12 @@ class TestNodeManager(base.BaseTestCase):
         utils.execute = mock.Mock(side_effect=fake_utils.execute_with_nm)
         self.nm = node_manager.NodeManager()
 
+    @classmethod
+    def tearDownClass(cls):
+        # reset inited to force an initialization of singleton for next test
+        node_manager.NodeManager()._inited = False
+        super(TestNodeManager, cls).tearDownClass()
+
     def test_read_power_all(self):
         power = self.nm.read_power_all()
 
@@ -52,7 +58,6 @@ class TestNodeManager(base.BaseTestCase):
         min_val = node_manager._hex(temperature["Minimum_value"])
         cur_val = node_manager._hex(temperature["Current_value"])
 
-        self.assertTrue(self.nm.nm_support)
         # see ipmi_test_data.py for raw data
         self.assertEqual(23, cur_val)
         self.assertEqual(22, min_val)
@@ -67,11 +72,17 @@ class TestNonNodeManager(base.BaseTestCase):
 
         utils.execute = mock.Mock(side_effect=fake_utils.execute_without_nm)
         self.nm = node_manager.NodeManager()
-        self.nm.nm_support = False
+
+    @classmethod
+    def tearDownClass(cls):
+        # reset inited to force an initialization of singleton for next test
+        node_manager.NodeManager()._inited = False
+        super(TestNonNodeManager, cls).tearDownClass()
 
     def test_read_power_all(self):
         power = self.nm.read_power_all()
 
+        self.assertFalse(self.nm.nm_support)
         # Non-Node Manager platform return empty data
         self.assertEqual({}, power)
 
diff --git a/ceilometer/tests/ipmi/platform/test_ipmi_sensor.py b/ceilometer/tests/ipmi/platform/test_ipmi_sensor.py
index 0fc4a8662..be2d2f8a6 100644
--- a/ceilometer/tests/ipmi/platform/test_ipmi_sensor.py
+++ b/ceilometer/tests/ipmi/platform/test_ipmi_sensor.py
@@ -13,13 +13,12 @@
 # under the License.
 
 import mock
+from oslotest import base
 
 from ceilometer.ipmi.platform import ipmi_sensor
 from ceilometer.tests.ipmi.platform import fake_utils
 from ceilometer import utils
 
-from oslotest import base
-
 
 class TestIPMISensor(base.BaseTestCase):
 
@@ -29,9 +28,16 @@ class TestIPMISensor(base.BaseTestCase):
         utils.execute = mock.Mock(side_effect=fake_utils.execute_with_nm)
         self.ipmi = ipmi_sensor.IPMISensor()
 
+    @classmethod
+    def tearDownClass(cls):
+        # reset inited to force an initialization of singleton for next test
+        ipmi_sensor.IPMISensor()._inited = False
+        super(TestIPMISensor, cls).tearDownClass()
+
     def test_read_sensor_temperature(self):
         sensors = self.ipmi.read_sensor_any('Temperature')
 
+        self.assertTrue(self.ipmi.ipmi_support)
         # only temperature data returned.
         self.assertIn('Temperature', sensors)
         self.assertEqual(1, len(sensors))
@@ -89,11 +95,17 @@ class TestNonIPMISensor(base.BaseTestCase):
 
         utils.execute = mock.Mock(side_effect=fake_utils.execute_without_ipmi)
         self.ipmi = ipmi_sensor.IPMISensor()
-        self.ipmi.ipmi_support = False
+
+    @classmethod
+    def tearDownClass(cls):
+        # reset inited to force an initialization of singleton for next test
+        ipmi_sensor.IPMISensor()._inited = False
+        super(TestNonIPMISensor, cls).tearDownClass()
 
     def test_read_sensor_temperature(self):
         sensors = self.ipmi.read_sensor_any('Temperature')
 
+        self.assertFalse(self.ipmi.ipmi_support)
         # Non-IPMI platform return empty data
         self.assertEqual({}, sensors)