diff --git a/opm/simulators/linalg/ISTLSolver.hpp b/opm/simulators/linalg/ISTLSolver.hpp
index c0b55dda17..45deee7339 100644
--- a/opm/simulators/linalg/ISTLSolver.hpp
+++ b/opm/simulators/linalg/ISTLSolver.hpp
@@ -161,9 +161,8 @@ std::unique_ptr<Matrix> blockJacobiAdjacency(const Grid& grid,
         using ElementMapper = GetPropType<TypeTag, Properties::ElementMapper>;
         constexpr static std::size_t pressureIndex = GetPropType<TypeTag, Properties::Indices>::pressureSwitchIdx;
 
-        enum { enableMICP = getPropValue<TypeTag, Properties::EnableMICP>() };
         enum { enablePolymerMolarWeight = getPropValue<TypeTag, Properties::EnablePolymerMW>() };
-        constexpr static bool isIncompatibleWithCprw = enableMICP || enablePolymerMolarWeight;
+        constexpr static bool isIncompatibleWithCprw = enablePolymerMolarWeight;
 
 #if HAVE_MPI
         using CommunicationType = Dune::OwnerOverlapCopyCommunication<int,int>;
@@ -218,16 +217,10 @@ std::unique_ptr<Matrix> blockJacobiAdjacency(const Grid& grid,
             OPM_TIMEBLOCK(IstlSolver);
 
             if (isIncompatibleWithCprw) {
-                // Some model variants are incompatible with the CPRW linear solver.
+                // Polymer injectivity is incompatible with the CPRW linear solver.
                 if (parameters_[0].linsolver_ == "cprw" || parameters_[0].linsolver_ == "hybrid") {
-                    std::string incompatible_model = "Unknown";
-                    if (enableMICP) {
-                        incompatible_model = "MICP";
-                    } else if (enablePolymerMolarWeight) {
-                        incompatible_model = "Polymer injectivity";
-                    }
                     OPM_THROW(std::runtime_error,
-                              incompatible_model + " model is incompatible with the CPRW linear solver.\n"
+                              "The polymer injectivity model is incompatible with the CPRW linear solver.\n"
                               "Choose a different option, for example --linear-solver=ilu0");
                 }
             }
diff --git a/opm/simulators/wells/StandardWellEquations.cpp b/opm/simulators/wells/StandardWellEquations.cpp
index 09f0e3c2d5..8fb29297e3 100644
--- a/opm/simulators/wells/StandardWellEquations.cpp
+++ b/opm/simulators/wells/StandardWellEquations.cpp
@@ -376,13 +376,13 @@ extractCPRPressureMatrix(PressureMatrix& jacobian,
             bweights[0][blockSz-1] = 1.0;
             diagElem = 1.0; // better scaling could have used the calculation below if weights were calculated
         } else {
-            for (std::size_t i = 0; i < cell_weights.size(); ++i) {
+            for (std::size_t i = 0; i < blockSz; ++i) {
                 bweights[0][i] = cell_weights[i];
             }
             bweights[0][blockSz-1] = 0.0;
             diagElem = 0.0;
             const auto& locmat = duneD_[0][0];
-            for (std::size_t i = 0; i < cell_weights.size(); ++i) {
+            for (std::size_t i = 0; i < blockSz; ++i) {
                 diagElem += locmat[i][bhp_var_index] * cell_weights[i];
             }
 
diff --git a/regressionTests.cmake b/regressionTests.cmake
index bbb5518e80..eb5b3dcbb0 100644
--- a/regressionTests.cmake
+++ b/regressionTests.cmake
@@ -1193,8 +1193,7 @@ add_test_compareECLFiles(CASENAME micp
                          SIMULATOR flow
                          ABS_TOL ${abs_tol}
                          REL_TOL ${rel_tol}
-                         DIR micp
-                         TEST_ARGS --linear-solver=ilu0)
+                         DIR micp)
 
 add_test_compareECLFiles(CASENAME 0_base_model6
                          FILENAME 0_BASE_MODEL6
@@ -1223,8 +1222,7 @@ add_test_compareECLFiles(CASENAME base_wt_tracer
                          ABS_TOL ${abs_tol}
                          REL_TOL ${rel_tol}
                          DIR tracer
-			 RESTART_STEP 1,3,7)
-
+                         RESTART_STEP 1,3,7)
 
 add_test_compareECLFiles(CASENAME min_bhp_1
                          FILENAME MIN_BHP_1