diff --git a/tests/correlators_test.py b/tests/correlators_test.py
index 47373f68..d2bb6a2c 100644
--- a/tests/correlators_test.py
+++ b/tests/correlators_test.py
@@ -31,6 +31,7 @@ def test_function_overloading():
             assert np.isclose(con[0].dvalue, t2.dvalue)
             assert np.allclose(con[0].deltas['t'], t2.deltas['t'])
 
+
 def test_modify_correlator():
     corr_content = []
     for t in range(24):
@@ -48,11 +49,14 @@ def test_modify_correlator():
     corr.deriv(symmetric=False)
     corr.second_deriv()
 
+
 def test_m_eff():
     my_corr = pe.correlators.Corr([pe.pseudo_Obs(10, 0.1, 't'), pe.pseudo_Obs(9, 0.05, 't'), pe.pseudo_Obs(8, 0.1, 't'), pe.pseudo_Obs(7, 0.05, 't')])
     my_corr.m_eff('log')
     my_corr.m_eff('cosh')
     my_corr.m_eff('sinh')
+    my_corr.m_eff('arccosh')
+
 
 def test_reweighting():
     my_corr = pe.correlators.Corr([pe.pseudo_Obs(10, 0.1, 't'), pe.pseudo_Obs(0, 0.05, 't')])
@@ -60,11 +64,21 @@ def test_reweighting():
     r_my_corr = my_corr.reweight(pe.pseudo_Obs(1, 0.1, 't'))
     assert r_my_corr.reweighted is True
 
+
+def test_correlate():
+    my_corr = pe.correlators.Corr([pe.pseudo_Obs(10, 0.1, 't'), pe.pseudo_Obs(0, 0.05, 't')])
+    corr1 = my_corr.correlate(my_corr)
+    corr2 = my_corr.correlate(my_corr[0])
+    with pytest.raises(Exception):
+        corr3 = my_corr.correlate(7.3)
+
+
 def test_T_symmetry():
     my_corr = pe.correlators.Corr([pe.pseudo_Obs(10, 0.1, 't'), pe.pseudo_Obs(0, 0.05, 't')])
     with pytest.warns(RuntimeWarning):
         T_symmetric = my_corr.T_symmetry(my_corr)
 
+
 def test_utility():
     corr_content = []
     for t in range(8):
diff --git a/tests/pyerrors_test.py b/tests/pyerrors_test.py
index 0966b06e..8f2ca2bd 100644
--- a/tests/pyerrors_test.py
+++ b/tests/pyerrors_test.py
@@ -238,18 +238,22 @@ def test_overloaded_functions():
 
 
 def test_utils():
-    my_obs = pe.pseudo_Obs(1.0, 0.5, 't')
-    my_obs.tag = "Test descrption"
-    my_obs.details(False)
-    my_obs.details(True)
-    assert not my_obs.is_zero_within_error()
-    my_obs.plot_tauint()
-    my_obs.plot_rho()
-    my_obs.plot_rep_dist()
-    my_obs.plot_history()
-    my_obs.plot_piechart()
-    assert my_obs > (my_obs - 1)
-    assert my_obs < (my_obs + 1)
+    my_obs = pe.pseudo_Obs(1.0, 0.5, 't|r01')
+    my_obs += pe.pseudo_Obs(1.0, 0.5, 't|r02')
+    for tau_exp in [0, 5]:
+        my_obs.gamma_method(tau_exp=tau_exp)
+        my_obs.tag = "Test description"
+        my_obs.details(False)
+        my_obs.details(True)
+        assert not my_obs.is_zero_within_error()
+        my_obs.plot_tauint()
+        my_obs.plot_rho()
+        my_obs.plot_rep_dist()
+        my_obs.plot_history(True)
+        my_obs.plot_history(False)
+        my_obs.plot_piechart()
+        assert my_obs > (my_obs - 1)
+        assert my_obs < (my_obs + 1)
 
 
 def test_cobs():