only:setDfcoDisabled

firmware/controllers/algo/engine.cpp

@@ -329,6 +329,7 @@ void Engine::resetLua() {
 	engineState.lua.fuelMult = 1;
 	engineState.lua.luaDisableEtb = false;
 	engineState.lua.luaIgnCut = false;
+	engineState.lua.disableDecelerationFuelCutOff = false;
 #if EFI_BOOST_CONTROL
 	module<BoostController>().unmock().resetLua();
 #endif // EFI_BOOST_CONTROL

firmware/controllers/algo/engine_state.txt

@@ -10,6 +10,7 @@ struct_no_prefix engine_state_s
 		bit luaDisableEtb
 		bit luaIgnCut
 		bit clutchDownState
+		bit disableDecelerationFuelCutOff
 	end_struct
 
 	struct speed_density_s

firmware/controllers/algo/fuel/dfco.cpp

@@ -1,6 +1,5 @@
 
-#include "engine_configuration.h"
-#include "sensor.h"
+#include "pch.h"
 
 #include "dfco.h"
 
@@ -17,6 +16,10 @@ bool DfcoController::getState() const {
 	if (!tps || !clt || !map) {
 		return false;
 	}
+	if (engine->engineState.lua.disableDecelerationFuelCutOff) {
+	  // Lua might have reasons to disable
+		return false;
+	}
 
 	float rpm = Sensor::getOrZero(SensorType::Rpm);
 	float vss = Sensor::getOrZero(SensorType::VehicleSpeed);

firmware/controllers/lua/lua_hooks.cpp

@@ -967,6 +967,10 @@ void configureRusefiLuaHooks(lua_State* lState) {
 		engine->engineState.lua.luaIgnCut = lua_toboolean(l, 1);
 		return 0;
 	});
+	lua_register(lState, "setDfcoDisabled", [](lua_State* l) {
+		engine->engineState.lua.disableDecelerationFuelCutOff = lua_toboolean(l, 1);
+		return 0;
+	});
 #endif // EFI_PROD_CODE
 
 	lua_register(lState, "setClutchUpState", [](lua_State* l) {