Something

  if(GetPlayerMenu(playerid) == Nitro) {
    if (IsValidMenu(Menu:Nitro)) {
    switch(row) {
    case 0: {
    AddVehicleComponent(GetPlayerVehicleID(playerid), 1008);
    ShowMenuForPlayer(Nitro, playerid);
    }
    case 1: {
    AddVehicleComponent(GetPlayerVehicleID(playerid), 1009);
    ShowMenuForPlayer(Nitro, playerid);
    }
    case 2: {
    AddVehicleComponent(GetPlayerVehicleID(playerid), 1010);
    ShowMenuForPlayer(Nitro, playerid);
    }
    case 3: {
    HideMenuForPlayer(Menu:Nitro, playerid);
    ShowMenuForPlayer(MainMod, playerid);
    }
  	}
  	}
    }