diff --git a/Source/Orts.Parsers.Msts/Interpolator.cs b/Source/Orts.Parsers.Msts/Interpolator.cs
index c0e79a869..c46e26b94 100644
--- a/Source/Orts.Parsers.Msts/Interpolator.cs
+++ b/Source/Orts.Parsers.Msts/Interpolator.cs
@@ -28,7 +28,7 @@ namespace Orts.Parsers.Msts
     public class Interpolator
     {
         float[] X;  // must be in increasing order
-        float[] Y;
+        public float[] Y;
         float[] Y2;
         int Size;       // number of values populated
         int PrevIndex;  // used to speed up repeated evaluations with similar x values
diff --git a/Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/PowerSupplies/DieselEngine.cs b/Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/PowerSupplies/DieselEngine.cs
index 60e8382e8..358d3d85d 100644
--- a/Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/PowerSupplies/DieselEngine.cs
+++ b/Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/PowerSupplies/DieselEngine.cs
@@ -864,7 +864,17 @@ public virtual void Parse(STFReader stf, MSTSDieselLocomotive loco)
                         break;
                     case "dieselpowertab": DieselPowerTab = new Interpolator(stf);initLevel |= SettingsFlags.DieselPowerTab; break;
                     case "dieselconsumptiontab": DieselConsumptionTab = new Interpolator(stf);initLevel |= SettingsFlags.DieselConsumptionTab; break;
-                    case "throttlerpmtab": ThrottleRPMTab = new Interpolator(stf); initLevel |= SettingsFlags.ThrottleRPMTab; break;
+                    case "throttlerpmtab":
+                        ThrottleRPMTab = new Interpolator(stf);
+                        initLevel |= SettingsFlags.ThrottleRPMTab;
+                        var size = ThrottleRPMTab.GetSize();
+                        var precY = ThrottleRPMTab.Y[0];
+                        for (int i = 1;  i < size; i++)
+                        {
+                            if (ThrottleRPMTab.Y[i] <= precY) ThrottleRPMTab.Y[i] = precY + 1;
+                            precY = ThrottleRPMTab.Y[i];
+                        }
+                        break;
                     case "dieseltorquetab": DieselTorqueTab = new Interpolator(stf); initLevel |= SettingsFlags.DieselTorqueTab; break;
                     case "minoilpressure": DieselMinOilPressurePSI = stf.ReadFloatBlock(STFReader.UNITS.PressureDefaultPSI, 0); initLevel |= SettingsFlags.MinOilPressure; break;
                     case "maxoilpressure": DieselMaxOilPressurePSI = stf.ReadFloatBlock(STFReader.UNITS.PressureDefaultPSI, 0); initLevel |= SettingsFlags.MaxOilPressure; break;