diff --git a/idaes/core/util/model_diagnostics.py b/idaes/core/util/model_diagnostics.py
index f298681de1..ad7166d866 100644
--- a/idaes/core/util/model_diagnostics.py
+++ b/idaes/core/util/model_diagnostics.py
@@ -1623,7 +1623,7 @@ def display_constraints_including_variable(self, variable, stream=None):
         # Get index of variable in Jacobian
         try:
             var_idx = self.nlp.get_primal_indices([variable])[0]
-        except (ValueError, PyomoException):
+        except (KeyError, PyomoException):
             raise AttributeError(f"Could not find {variable.name} in model.")
 
         nonzeros = self.jacobian.getcol(var_idx).nonzero()
@@ -1670,7 +1670,7 @@ def display_variables_in_constraint(self, constraint, stream=None):
         # Get index of variable in Jacobian
         try:
             con_idx = self.nlp.get_constraint_indices([constraint])[0]
-        except ValueError:
+        except KeyError:
             raise AttributeError(f"Could not find {constraint.name} in model.")
 
         nonzeros = self.jacobian[con_idx, :].nonzero()
@@ -1678,7 +1678,9 @@ def display_variables_in_constraint(self, constraint, stream=None):
         # Build a list of all vars in constraint
         vars_in_cons = []
         for c in nonzeros[1]:
-            vars_in_cons.append(f"{self.var_list[c].name}: {self.jacobian[(con_idx, c)]:.3e}")
+            vars_in_cons.append(
+                f"{self.var_list[c].name}: {self.jacobian[(con_idx, c)]:.3e}"
+            )
 
         # Write the output
         _write_report_section(
diff --git a/idaes/core/util/tests/test_model_diagnostics.py b/idaes/core/util/tests/test_model_diagnostics.py
index fe59206ad9..d6952e93d6 100644
--- a/idaes/core/util/tests/test_model_diagnostics.py
+++ b/idaes/core/util/tests/test_model_diagnostics.py
@@ -1588,8 +1588,8 @@ def test_display_constraints_including_variable(self):
         expected = """====================================================================================
 The following constraints involve v[1]:
 
-    c1: 1.0
-    c4: 8.0
+    c1: 1.000e+00
+    c4: 8.000e+00
 
 ====================================================================================
 """
@@ -1653,8 +1653,8 @@ def test_display_variables_in_constraint(self):
         expected = """====================================================================================
 The following variables are involved in c1:
 
-    v[1]: 1.0
-    v[2]: 2.0
+    v[1]: 1.000e+00
+    v[2]: 2.000e+00
 
 ====================================================================================
 """