diff --git a/src/systems/abstractsystem.jl b/src/systems/abstractsystem.jl
index 8753b30656..c808aa4057 100644
--- a/src/systems/abstractsystem.jl
+++ b/src/systems/abstractsystem.jl
@@ -819,24 +819,22 @@ namespace_controls(sys::AbstractSystem) = controls(sys, controls(sys))
 
 function namespace_defaults(sys)
     defs = defaults(sys)
-    Dict((isparameter(k) ? parameters(sys, k) : unknowns(sys, k)) => namespace_expr(
-             v, sys; check = true)
+    Dict((isparameter(k) ? parameters(sys, k) : unknowns(sys, k)) => namespace_expr(v, sys)
     for (k, v) in pairs(defs))
 end
 
 function namespace_equations(sys::AbstractSystem, ivs = independent_variables(sys))
     eqs = equations(sys)
     isempty(eqs) && return Equation[]
-    map(eq -> namespace_equation(eq, sys; ivs, check = true), eqs)
+    map(eq -> namespace_equation(eq, sys; ivs), eqs)
 end
 
 function namespace_equation(eq::Equation,
         sys,
         n = nameof(sys);
-        ivs = independent_variables(sys),
-        check = false)
-    _lhs = namespace_expr(eq.lhs, sys, n; ivs, check)
-    _rhs = namespace_expr(eq.rhs, sys, n; ivs, check)
+        ivs = independent_variables(sys))
+    _lhs = namespace_expr(eq.lhs, sys, n; ivs)
+    _rhs = namespace_expr(eq.rhs, sys, n; ivs)
     _lhs ~ _rhs
 end
 
@@ -846,36 +844,32 @@ function namespace_assignment(eq::Assignment, sys)
     Assignment(_lhs, _rhs)
 end
 
-function namespace_expr(
-        O, sys, n = nameof(sys); ivs = independent_variables(sys), check = false)
+function namespace_expr(O, sys, n = nameof(sys); ivs = independent_variables(sys))
     O = unwrap(O)
     if any(isequal(O), ivs)
         return O
     elseif istree(O)
         T = typeof(O)
         renamed = let sys = sys, n = n, T = T
-            map(a -> namespace_expr(a, sys, n; ivs, check)::Any, arguments(O))
+            map(a -> namespace_expr(a, sys, n; ivs)::Any, arguments(O))
         end
         if isvariable(O)
-            check && !is_variable(sys, O) && !is_parameter(sys, O) && return O
             # Use renamespace so the scope is correct, and make sure to use the
             # metadata from the rescoped variable
             rescoped = renamespace(n, O)
             similarterm(O, operation(rescoped), renamed,
                 metadata = metadata(rescoped))
         elseif Symbolics.isarraysymbolic(O)
-            check && !is_variable(sys, O) && !is_parameter(sys, O) && return O
             # promote_symtype doesn't work for array symbolics
             similarterm(O, operation(O), renamed, symtype(O), metadata = metadata(O))
         else
             similarterm(O, operation(O), renamed, metadata = metadata(O))
         end
     elseif isvariable(O)
-        check && !is_variable(sys, O) && !is_parameter(sys, O) && return O
         renamespace(n, O)
     elseif O isa Array
         let sys = sys, n = n
-            map(o -> namespace_expr(o, sys, n; ivs, check), O)
+            map(o -> namespace_expr(o, sys, n; ivs), O)
         end
     else
         O
diff --git a/test/odesystem.jl b/test/odesystem.jl
index ee4b22f5fc..f45987cdc5 100644
--- a/test/odesystem.jl
+++ b/test/odesystem.jl
@@ -995,61 +995,3 @@ let # Issue https://github.com/SciML/ModelingToolkit.jl/issues/2322
     sol = solve(prob, Rodas4())
     @test sol(1)[]≈0.6065307685451087 rtol=1e-4
 end
-
-# Issue#2344
-function FML2(; name)
-    @parameters begin
-        k2[1:1] = [1.0]
-    end
-    systems = @named begin
-        constant = Constant(k = k2[1])
-    end
-    @variables begin
-        x(t) = 0
-    end
-    eqs = [
-        D(x) ~ constant.output.u + k2[1]
-    ]
-    ODESystem(eqs, t; systems, name)
-end
-
-@mtkbuild model = FML2()
-
-@test isequal(ModelingToolkit.defaults(model)[model.constant.k], model.k2[1])
-@test_nowarn ODEProblem(model, [], (0.0, 10.0))
-
-# Issue#2477
-function RealExpression(; name, y)
-    vars = @variables begin
-        u(t)
-    end
-    eqns = [
-        u ~ y
-    ]
-    sys = ODESystem(eqns, t, vars, []; name)
-end
-
-function sys1(; name)
-    vars = @variables begin
-        x(t)
-        z(t)[1:1]
-    end # doing a collect on z doesn't work either. 
-    @named e1 = RealExpression(y = x) # This works perfectly. 
-    @named e2 = RealExpression(y = z[1]) # This bugs. However, `full_equations(e2)` works as expected. 
-    systems = [e1, e2]
-    ODESystem(Equation[], t, Iterators.flatten(vars), []; systems, name)
-end
-
-@named sys = sys1()
-sys = complete(sys)
-@test Set(equations(sys)) == Set([sys.e1.u ~ sys.x, sys.e2.u ~ sys.z[1]])
-
-# Issue#2522
-@parameters a[1:2]=[1, 2] b=4 c=1
-@variables x(t)=ParentScope(a[1]) y(t)=ParentScope(b)
-@named level0 = ODESystem([D(x) ~ ParentScope(a[2]),
-        D(y) ~ ParentScope(c)], t, [x, y], [])
-level1 = ODESystem(Equation[], t, [], [a..., b, c]; name = :level1) ∘ level0
-level1 = structural_simplify(level1)
-@test isequal(ModelingToolkit.defaults(level1)[level1.level0.x], level1.a[1])
-@test_nowarn ODEProblem(level1, [], (0, 1))