diff --git a/preprocessor/ComputingTasks.cc b/preprocessor/ComputingTasks.cc
index 75fc41bb2..10fcb6b3d 100644
--- a/preprocessor/ComputingTasks.cc
+++ b/preprocessor/ComputingTasks.cc
@@ -79,8 +79,8 @@ void ModelInfoStatement::writeOutput(ostream &output, const string &basename) co
 }
 
 
-SimulStatement::SimulStatement(const OptionsList &options_list_arg, bool block_arg, bool byte_code_arg) :
-  options_list(options_list_arg), byte_code(byte_code_arg), block(block_arg)
+SimulStatement::SimulStatement(const OptionsList &options_list_arg) :
+  options_list(options_list_arg)
 {
 }
 
@@ -98,11 +98,9 @@ SimulStatement::writeOutput(ostream &output, const string &basename) const
 }
 
 StochSimulStatement::StochSimulStatement(const SymbolList &symbol_list_arg,
-                                         const OptionsList &options_list_arg,
-                                         bool block_arg) :
+                                         const OptionsList &options_list_arg) :
   symbol_list(symbol_list_arg),
-  options_list(options_list_arg),
-  block(block_arg)
+  options_list(options_list_arg)
 {
 }
 
@@ -130,10 +128,7 @@ StochSimulStatement::writeOutput(ostream &output, const string &basename) const
 {
   options_list.writeOutput(output);
   symbol_list.writeOutput("var_list_", output);
-  if (!block)
-    output << "info = stoch_simul(var_list_);" << endl;
-  else
-    output << "info = stoch_simul_sparse(var_list_);" << endl;
+  output << "info = stoch_simul(var_list_);" << endl;
 }
 
 ForecastStatement::ForecastStatement(const SymbolList &symbol_list_arg,
diff --git a/preprocessor/ComputingTasks.hh b/preprocessor/ComputingTasks.hh
index 0ffe3c6f8..6fc7e61c5 100644
--- a/preprocessor/ComputingTasks.hh
+++ b/preprocessor/ComputingTasks.hh
@@ -52,10 +52,8 @@ class SimulStatement : public Statement
 {
 private:
   const OptionsList options_list;
-  const bool byte_code;
-  const bool block;
 public:
-  SimulStatement(const OptionsList &options_list_arg, bool block_arg, bool byte_code_arg);
+  SimulStatement(const OptionsList &options_list_arg);
   virtual void checkPass(ModFileStructure &mod_file_struct);
   virtual void writeOutput(ostream &output, const string &basename) const;
 };
@@ -75,11 +73,9 @@ class StochSimulStatement : public Statement
 private:
   const SymbolList symbol_list;
   const OptionsList options_list;
-  bool block;
 public:
   StochSimulStatement(const SymbolList &symbol_list_arg,
-                      const OptionsList &options_list_arg,
-                      bool block_arg);
+                      const OptionsList &options_list_arg);
   virtual void checkPass(ModFileStructure &mod_file_struct);
   virtual void writeOutput(ostream &output, const string &basename) const;
 };
diff --git a/preprocessor/ModFile.cc b/preprocessor/ModFile.cc
index e9e87af61..b0e3e2e6d 100644
--- a/preprocessor/ModFile.cc
+++ b/preprocessor/ModFile.cc
@@ -154,6 +154,9 @@ void
 ModFile::computingPass(bool no_tmp_terms)
 {
   // Mod file may have no equation (for example in a standalone BVAR estimation)
+  bool dynamic_model_needed = mod_file_struct.simul_present || mod_file_struct.check_present || mod_file_struct.stoch_simul_present
+                         || mod_file_struct.estimation_present|| mod_file_struct.forecast_present || mod_file_struct.osr_present
+                         || mod_file_struct.ramsey_policy_present;
   if (dynamic_model.equation_number() > 0)
     {
       // Compute static model and its derivatives
@@ -168,21 +171,25 @@ ModFile::computingPass(bool no_tmp_terms)
           static_model.computingPass(block, false, no_tmp_terms);
         }
       // Set things to compute for dynamic model
-
-      if (mod_file_struct.simul_present)
-        dynamic_model.computingPass(false, false, false, false, global_eval_context, no_tmp_terms, block, use_dll);
-      else
+      if (dynamic_model_needed)
         {
-          if (mod_file_struct.order_option < 1 || mod_file_struct.order_option > 3)
+          if (mod_file_struct.simul_present)
+            dynamic_model.computingPass(false, false, false, false, global_eval_context, no_tmp_terms, block, use_dll);
+          else
             {
-              cerr << "ERROR: Incorrect order option..." << endl;
-              exit(EXIT_FAILURE);
+              if (mod_file_struct.order_option < 1 || mod_file_struct.order_option > 3)
+                {
+                  cerr << "ERROR: Incorrect order option..." << endl;
+                  exit(EXIT_FAILURE);
+                }
+              bool hessian = mod_file_struct.order_option >= 2;
+              bool thirdDerivatives = mod_file_struct.order_option == 3;
+              bool paramsDerivatives = mod_file_struct.identification_present;
+              dynamic_model.computingPass(true, hessian, thirdDerivatives, paramsDerivatives, global_eval_context, no_tmp_terms, false, use_dll);
             }
-          bool hessian = mod_file_struct.order_option >= 2;
-          bool thirdDerivatives = mod_file_struct.order_option == 3;
-          bool paramsDerivatives = mod_file_struct.identification_present;
-          dynamic_model.computingPass(true, hessian, thirdDerivatives, paramsDerivatives, global_eval_context, no_tmp_terms, false, use_dll);
         }
+      else
+        dynamic_model.computingPass(true, false, false, false, global_eval_context, no_tmp_terms, false, false);
     }
 
   for(vector<Statement *>::iterator it = statements.begin();
@@ -194,7 +201,9 @@ void
 ModFile::writeOutputFiles(const string &basename, bool clear_all) const
 {
   ofstream mOutputFile;
-
+  bool dynamic_model_needed = mod_file_struct.simul_present || mod_file_struct.check_present || mod_file_struct.stoch_simul_present
+                         || mod_file_struct.estimation_present|| mod_file_struct.forecast_present || mod_file_struct.osr_present
+                         || mod_file_struct.ramsey_policy_present;
   if (basename.size())
     {
       string fname(basename);
@@ -269,7 +278,10 @@ ModFile::writeOutputFiles(const string &basename, bool clear_all) const
 
   if (dynamic_model.equation_number() > 0)
     {
-      dynamic_model.writeOutput(mOutputFile, basename, block, byte_code, use_dll);
+      if(dynamic_model_needed)
+        dynamic_model.writeOutput(mOutputFile, basename, block, byte_code, use_dll);
+      else
+        dynamic_model.writeOutput(mOutputFile, basename, false, false, false);
       if (!byte_code)
         static_model.writeOutput(mOutputFile, block);
     }
@@ -296,8 +308,16 @@ ModFile::writeOutputFiles(const string &basename, bool clear_all) const
         static_dll_model.writeStaticFile(basename, block);
       else
         static_model.writeStaticFile(basename, block);
-      dynamic_model.writeDynamicFile(basename, block, byte_code, use_dll);
-      dynamic_model.writeParamsDerivativesFile(basename);
+      if(dynamic_model_needed)
+        {
+          dynamic_model.writeDynamicFile(basename, block, byte_code, use_dll);
+          dynamic_model.writeParamsDerivativesFile(basename);
+        }
+      else
+        {
+          /*dynamic_model.writeDynamicFile(basename, false, false, false);
+          dynamic_model.writeParamsDerivativesFile(basename);*/
+        }
     }
 
   cout << "done" << endl;
diff --git a/preprocessor/ParsingDriver.cc b/preprocessor/ParsingDriver.cc
index 3c32058bc..efdf6fa11 100644
--- a/preprocessor/ParsingDriver.cc
+++ b/preprocessor/ParsingDriver.cc
@@ -694,7 +694,7 @@ void ParsingDriver::rplot()
 
 void ParsingDriver::stoch_simul()
 {
-  mod_file->addStatement(new StochSimulStatement(symbol_list, options_list, mod_file->block));
+  mod_file->addStatement(new StochSimulStatement(symbol_list, options_list));
   symbol_list.clear();
   options_list.clear();
 }
@@ -702,7 +702,7 @@ void ParsingDriver::stoch_simul()
 void
 ParsingDriver::simul()
 {
-  mod_file->addStatement(new SimulStatement(options_list, mod_file->block, mod_file->byte_code));
+  mod_file->addStatement(new SimulStatement(options_list));
   options_list.clear();
 }