diff --git a/test/porousmediumflow/1p/implicit/1pniconvectionproblem.hh b/test/porousmediumflow/1p/implicit/1pniconvectionproblem.hh
index af9064770c4c1d0a2f14e81ac35fc7ec1d1c700b..0ca5a8cc0ce4962fb7156bb5dac96c456841c590 100644
--- a/test/porousmediumflow/1p/implicit/1pniconvectionproblem.hh
+++ b/test/porousmediumflow/1p/implicit/1pniconvectionproblem.hh
@@ -55,7 +55,7 @@ NEW_TYPE_TAG(OnePNIConvectionCCTpfaTypeTag, INHERITS_FROM(CCTpfaModel, OnePNICon
 NEW_TYPE_TAG(OnePNIConvectionCCMpfaTypeTag, INHERITS_FROM(CCMpfaModel, OnePNIConvectionTypeTag));
 
 // Set the grid type
-SET_TYPE_PROP(OnePNIConvectionTypeTag, Grid, Dune::YaspGrid<2>);
+SET_TYPE_PROP(OnePNIConvectionTypeTag, Grid, Dune::YaspGrid<1>);
 
 // Set the problem property
 SET_TYPE_PROP(OnePNIConvectionTypeTag, Problem, OnePNIConvectionProblem<TypeTag>);
diff --git a/test/porousmediumflow/1p/implicit/CMakeLists.txt b/test/porousmediumflow/1p/implicit/CMakeLists.txt
index 61f36568ffde0ab2d4be19a3090789a1ea388512..d021037df340eede379d9c43e0ec25fb9212f3da 100644
--- a/test/porousmediumflow/1p/implicit/CMakeLists.txt
+++ b/test/porousmediumflow/1p/implicit/CMakeLists.txt
@@ -58,8 +58,8 @@ dune_add_test(NAME test_1pnibox_convection
               COMPILE_DEFINITIONS TYPETAG=OnePNIConvectionBoxTypeTag
               COMMAND ${CMAKE_SOURCE_DIR}/bin/testing/runtest.py
               CMD_ARGS --script fuzzy
-                       --files ${CMAKE_SOURCE_DIR}/test/references/1pniboxconvection-reference.vtu
-                               ${CMAKE_CURRENT_BINARY_DIR}/1pnibox_convection-00009.vtu
+                       --files ${CMAKE_SOURCE_DIR}/test/references/1pniboxconvection-reference.vtp
+                               ${CMAKE_CURRENT_BINARY_DIR}/1pnibox_convection-00009.vtp
                        --command "${CMAKE_CURRENT_BINARY_DIR}/test_1pnibox_convection test_1pnifv_convection.input -Problem.Name 1pnibox_convection"
                        --zeroThreshold {"velocity":1e-15})
 
@@ -78,8 +78,8 @@ dune_add_test(NAME test_1pnicctpfa_convection
               COMPILE_DEFINITIONS TYPETAG=OnePNIConvectionCCTpfaTypeTag
               COMMAND ${CMAKE_SOURCE_DIR}/bin/testing/runtest.py
               CMD_ARGS --script fuzzy
-                       --files ${CMAKE_SOURCE_DIR}/test/references/1pniccconvection-reference.vtu
-                               ${CMAKE_CURRENT_BINARY_DIR}/1pnicctpfa_convection-00009.vtu
+                       --files ${CMAKE_SOURCE_DIR}/test/references/1pniccconvection-reference.vtp
+                               ${CMAKE_CURRENT_BINARY_DIR}/1pnicctpfa_convection-00009.vtp
                        --command "${CMAKE_CURRENT_BINARY_DIR}/test_1pnicctpfa_convection test_1pnifv_convection.input -Problem.Name 1pnicctpfa_convection")
 
 dune_add_test(NAME test_1pniccmpfa_conduction
@@ -91,15 +91,6 @@ dune_add_test(NAME test_1pniccmpfa_conduction
                                ${CMAKE_CURRENT_BINARY_DIR}/1pniccmpfa_conduction-00005.vtu
                        --command "${CMAKE_CURRENT_BINARY_DIR}/test_1pniccmpfa_conduction test_1pnifv_conduction.input -Problem.Name 1pniccmpfa_conduction")
 
-dune_add_test(NAME test_1pniccmpfa_convection
-              SOURCES test_1pnifv.cc
-              COMPILE_DEFINITIONS TYPETAG=OnePNIConvectionCCMpfaTypeTag
-              COMMAND ${CMAKE_SOURCE_DIR}/bin/testing/runtest.py
-              CMD_ARGS --script fuzzy
-                       --files ${CMAKE_SOURCE_DIR}/test/references/ccmpfa1pniconvection-reference.vtu
-                               ${CMAKE_CURRENT_BINARY_DIR}/1pniccmpfa_convection-00009.vtu
-                       --command "${CMAKE_CURRENT_BINARY_DIR}/test_1pniccmpfa_convection test_1pnifv_convection.input -Problem.Name 1pniccmpfa_convection")
-
 # dim < dimWorld tests with Dune::Foamgrid<1,3>
 dune_add_test(NAME test_1pcctpfa_network1d3d
               SOURCES test_1pfv_network1d3d.cc
diff --git a/test/porousmediumflow/1p/implicit/test_1pnifv.cc b/test/porousmediumflow/1p/implicit/test_1pnifv.cc
index 41b729e46e813a5d50c4830e733f1dfa5d81844b..5ca82d837bbef3385eef014b6e47b2fd8ab708fc 100644
--- a/test/porousmediumflow/1p/implicit/test_1pnifv.cc
+++ b/test/porousmediumflow/1p/implicit/test_1pnifv.cc
@@ -116,6 +116,12 @@ int main(int argc, char** argv) try
     const std::string paramGroup = FVGridGeometry::discMethod == DiscretizationMethod::ccmpfa ? "MpfaTest" : "";
     auto problem = std::make_shared<Problem>(fvGridGeometry, paramGroup);
 
+    // get some time loop parameters
+    using Scalar = typename GET_PROP_TYPE(TypeTag, Scalar);
+    const auto tEnd = getParam<Scalar>("TimeLoop.TEnd");
+    const auto maxDt = getParam<Scalar>("TimeLoop.MaxTimeStepSize");
+    auto dt = getParam<Scalar>("TimeLoop.DtInitial");
+
     // the solution vector
     using SolutionVector = typename GET_PROP_TYPE(TypeTag, SolutionVector);
     SolutionVector x(fvGridGeometry->numDofs());
@@ -127,17 +133,6 @@ int main(int argc, char** argv) try
     auto gridVariables = std::make_shared<GridVariables>(problem, fvGridGeometry);
     gridVariables->init(x, xOld);
 
-    // get some time loop parameters
-    using Scalar = typename GET_PROP_TYPE(TypeTag, Scalar);
-    const auto tEnd = getParam<Scalar>("TimeLoop.TEnd");
-    const auto maxDt = getParam<Scalar>("TimeLoop.MaxTimeStepSize");
-    auto dt = getParam<Scalar>("TimeLoop.DtInitial");
-
-    // check if we are about to restart a previously interrupted simulation
-    Scalar restartTime = 0;
-    if (Parameters::getTree().hasKey("Restart") || Parameters::getTree().hasKey("TimeLoop.Restart"))
-        restartTime = getParam<Scalar>("TimeLoop.Restart");
-
     // intialize the vtk output module
     using VtkOutputFields = typename GET_PROP_TYPE(TypeTag, VtkOutputFields);
     VtkOutputModule<GridVariables, SolutionVector> vtkWriter(*gridVariables, x, problem->name());
@@ -151,7 +146,7 @@ int main(int argc, char** argv) try
     const int vtkOutputInterval = getParam<int>("Problem.OutputInterval");
 
     // instantiate time loop
-    auto timeLoop = std::make_shared<TimeLoop<Scalar>>(restartTime, dt, tEnd);
+    auto timeLoop = std::make_shared<TimeLoop<Scalar>>(0.0, dt, tEnd);
     timeLoop->setMaxTimeStepSize(maxDt);
 
     // the assembler with time loop for instationary problem
diff --git a/test/porousmediumflow/1p/implicit/test_1pnifv_convection.input b/test/porousmediumflow/1p/implicit/test_1pnifv_convection.input
index 1bab248e671fa7bec7d00c97fa21ee9eed5c4fd8..973b86a0eff8909769685676d00ffd8081b8e428 100644
--- a/test/porousmediumflow/1p/implicit/test_1pnifv_convection.input
+++ b/test/porousmediumflow/1p/implicit/test_1pnifv_convection.input
@@ -4,12 +4,12 @@ TEnd = 3e4 # [s]
 MaxTimeStepSize = 1e3
 
 [Grid]
-LowerLeft = 0 0
-UpperRight = 20 1
-Cells = 80 1
+LowerLeft = 0
+UpperRight = 20
+Cells = 80
 
 [Problem]
-Name = 1pnifv_conduction # name passed to the output routines
+Name = 1pnifv_convection # name passed to the output routines
 OutputInterval = 5 # every 5th timestep an output file is written
 DarcyVelocity = 1e-4 # [m/s] inflow at the left boundary
 EnableGravity = false # Disable gravity
@@ -22,5 +22,5 @@ AddVelocity = false # enable velocity output
 
 [Component]
 SolidDensity = 2700
-solidThermalConductivity = 2.8
-solidHeatCapacity = 790
+SolidThermalConductivity = 2.8
+SolidHeatCapacity = 790
diff --git a/test/references/1pniboxconvection-reference.vtp b/test/references/1pniboxconvection-reference.vtp
new file mode 100644
index 0000000000000000000000000000000000000000..ec90366ab433e79e8b9d6ac3470d68a20732f765
--- /dev/null
+++ b/test/references/1pniboxconvection-reference.vtp
@@ -0,0 +1,108 @@
+<?xml version="1.0"?>
+<VTKFile type="PolyData" version="0.1" byte_order="LittleEndian">
+  <PolyData>
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+      <PointData Scalars="p">
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+        <DataArray type="Float32" Name="temperatureExact" NumberOfComponents="1" format="ascii">
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+      </PointData>
+      <CellData Scalars="velocity_H2O (m/s)">
+        <DataArray type="Float32" Name="velocity_H2O (m/s)" NumberOfComponents="1" format="ascii">
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+        <DataArray type="Float32" Name="process rank" NumberOfComponents="1" format="ascii">
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+      </CellData>
+      <Points>
+        <DataArray type="Float32" Name="Coordinates" NumberOfComponents="3" format="ascii">
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+      </Points>
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+        <DataArray type="Int32" Name="connectivity" NumberOfComponents="1" format="ascii">
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+        <DataArray type="Int32" Name="offsets" NumberOfComponents="1" format="ascii">
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+  </PolyData>
+</VTKFile>
diff --git a/test/references/1pniboxconvection-reference.vtu b/test/references/1pniboxconvection-reference.vtu
deleted file mode 100644
index 5c0e668a8178b235721846ba2f466c9d369f2b34..0000000000000000000000000000000000000000
--- a/test/references/1pniboxconvection-reference.vtu
+++ /dev/null
@@ -1,205 +0,0 @@
-<?xml version="1.0"?>
-<VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian">
-  <UnstructuredGrid>
-    <Piece NumberOfCells="80" NumberOfPoints="162">
-      <PointData Scalars="p" Vectors="velocity">
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diff --git a/test/references/ccmpfa1pniconvection-reference.vtu b/test/references/ccmpfa1pniconvection-reference.vtu
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