diff --git a/tox.ini b/tox.ini
index e123d64..a004c6e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -28,6 +28,10 @@
 commands = {posargs}
 
 [testenv:cover]
+commands = rm -rf *.pyc
+           rm -rf cover
+           rm -f .coverage
+           nosetests {posargs}
 setenv = VIRTUAL_ENV={envdir}
          NOSE_WITH_COVERAGE=1
          NOSE_COVER_BRANCHES=1
@@ -36,7 +40,7 @@
          NOSE_COVER_HTML_DIR={toxinidir}/cover
          NOSE_WHERE=patrole_tempest_plugin/tests/unit
 whitelist_externals = nosetests
-commands = nosetests {posargs}
+                      rm
 
 [testenv:docs]
 commands = python setup.py build_sphinx