diff --git a/rebar.config b/rebar.config
index 9fc9ffb..4f1b4c8 100644
--- a/rebar.config
+++ b/rebar.config
@@ -78,7 +78,6 @@
                , unmatched_returns
                , error_handling
                ]},
-    {get_warnings, true},
     {plt_apps, top_level_deps},
     {plt_extra_apps, []},
     {plt_location, local},
diff --git a/src/wpool_fsm_process.erl b/src/wpool_fsm_process.erl
index 1961ce3..7682b56 100644
--- a/src/wpool_fsm_process.erl
+++ b/src/wpool_fsm_process.erl
@@ -140,7 +140,7 @@ code_change(OldVsn, StateName, State, Extra) ->
       {ok, dispatch_state, State#state{ state = NewState
                                       , fsm_state = NextStateName
                                       }};
-    Error -> {error, Error}
+    _Error -> {ok, dispatch_state, State}
   end.
 
 %% @private
diff --git a/src/wpool_fsm_worker.erl b/src/wpool_fsm_worker.erl
index 62c6200..13b1046 100644
--- a/src/wpool_fsm_worker.erl
+++ b/src/wpool_fsm_worker.erl
@@ -130,11 +130,25 @@ handle_sync_event(Event, _From, StateName, StateData) ->
 %%%===================================================================
 %% @private
 -spec common_state(term(), term()) -> {next_state, common_state, term()}.
+common_state(timeout, StateData) -> {next_state, common_state, StateData};
 common_state(Msg, StateData) -> handle_event(Msg, common_state, StateData).
 
 %% @private
 -spec common_state(term(), term(), term()) ->
         {reply, term(), common_state, term()}.
+common_state(stop, _From, StateData) ->
+  {stop, normal, ok, StateData};
+common_state(stop_without_reply, From, StateData) ->
+  gen_fsm:reply(From, ok),
+  {stop, normal, StateData};
+common_state({timeout, Timeout}, _From, StateData) ->
+  {reply, ok,  common_state, StateData, Timeout};
+common_state(next_state, From, StateData) ->
+  gen_fsm:reply(From, ok),
+  {next_state, common_state, StateData};
+common_state({next_state, Timeout}, From, StateData) ->
+  gen_fsm:reply(From, ok),
+  {next_state, common_state, StateData, Timeout};
 common_state(Msg, From, StateData) ->
   handle_sync_event(Msg, From, common_state, StateData).
 
diff --git a/test/echo_fsm.erl b/test/echo_fsm.erl
index 4130c0a..c7149be 100644
--- a/test/echo_fsm.erl
+++ b/test/echo_fsm.erl
@@ -21,6 +21,7 @@
         , handle_sync_event/4
         , terminate/3
         , code_change/4
+        , format_status/2
         ]).
 -export([ state_one/2
         , state_two/2
@@ -35,12 +36,16 @@
 init(Something) -> Something.
 
 -spec state_one(Event, any()) -> Event.
+state_one(timeout, LoopData) ->
+  {next_state, state_one, LoopData};
 state_one(Event, _LoopData) -> Event.
 
 -spec state_one(Event, any(), any()) -> Event.
 state_one(Event, _From, _LoopData) -> Event.
 
 -spec state_two(Event, any()) -> Event.
+state_two(timeout, LoopData) ->
+  {next_state, state_two, LoopData};
 state_two(Event, _LoopData) -> Event.
 
 -spec state_two(Event, any(), any()) -> Event.
@@ -55,12 +60,26 @@ handle_event(Event, _StateName, _StateData) -> Event.
 -spec handle_sync_event(any(), any(), any(), any()) -> any().
 handle_sync_event(state, _From, StateName, StateData) ->
   {reply, StateData, StateName, StateData};
+handle_sync_event({next_state, NextState, NewStateData}
+    , From, _StateName, _StateData) ->
+  gen_fsm:reply(From, ok),
+  {next_state, NextState, NewStateData};
+handle_sync_event({next_state, NextState, NewStateData, Timeout}
+    , From, _StateName, _StateData) ->
+  gen_fsm:reply(From, ok),
+  {next_state, NextState, NewStateData, Timeout};
+handle_sync_event({stop, Reason, StateData}
+    , From, _StateName, _StateData) ->
+  gen_fsm:reply(From, ok),
+  {stop, Reason, StateData};
 handle_sync_event(Event, _From, _StateName, _StateData) ->
   Event.
 
 -spec terminate(any(), any(), any()) -> ok.
 terminate(_Reason, _StateName, _StateData) -> ok.
 
--spec code_change(any(), any(), any(), any()) -> {ok, state_one, term()}.
-code_change(_OldVsn, _StateName, StateData, _Extra) ->
-  {ok, state_one, StateData}.
+-spec code_change(any(), any(), any(), any()) -> any().
+code_change(_OldVsn, _StateName, _StateData, Extra) -> Extra.
+
+-spec format_status(normal | terminate, [list() | term()]) -> term().
+  format_status(_Opt, [_PDict, StateData]) -> StateData.
diff --git a/test/wpool_fsm_pool_SUITE.erl b/test/wpool_fsm_pool_SUITE.erl
index 9e0ad27..8b2b429 100644
--- a/test/wpool_fsm_pool_SUITE.erl
+++ b/test/wpool_fsm_pool_SUITE.erl
@@ -161,6 +161,21 @@ available_worker(_Config) ->
   {?WORKERS, UniqueWorkers, true} =
     {?WORKERS, UniqueWorkers, (?WORKERS/2) >= length(UniqueWorkers)},
 
+  ct:log(
+    "We put all the workers to run again and test how manage
+    the messages on the queue"),
+  [wpool:send_event(
+    Pool, {timer, sleep, [2000]}) || _ <- lists:seq(1, ?WORKERS)],
+  ok = wpool:sync_send_event(Pool, {timeout, 0}, available_worker, 10000),
+  [wpool:send_event(
+    Pool, {timer, sleep, [2000]}) || _ <- lists:seq(1, ?WORKERS)],
+  ok = wpool:sync_send_event(Pool, stop, available_worker, 10000),
+  [wpool:send_event(
+    Pool, {timer, sleep, [2000]}) || _ <- lists:seq(1, ?WORKERS)],
+  ok = wpool:sync_send_event(Pool, next_state, available_worker, 10000),
+  ok = wpool:sync_send_event(Pool, {next_state, 0}, available_worker, 10000),
+  ok = wpool:sync_send_event(Pool, stop_without_reply, available_worker, 10000),
+
   {comment, []}.
 
 -spec best_worker(config()) -> {comment, []}.
diff --git a/test/wpool_fsm_process_SUITE.erl b/test/wpool_fsm_process_SUITE.erl
index c6a2e92..9417f6b 100644
--- a/test/wpool_fsm_process_SUITE.erl
+++ b/test/wpool_fsm_process_SUITE.erl
@@ -29,6 +29,7 @@
         , info/1
         , async_states/1
         , sync_states/1
+        , complete_coverage/1
         ]).
 
 -spec all() -> [atom()].
@@ -73,6 +74,8 @@ init_timeout(_Config) ->
     wpool_fsm_process:start_link(
       ?MODULE, echo_fsm, {ok, state_one, [], 0}, []),
   timer:sleep(1),
+  Pid ! {stop, normal, state},
+  timer:sleep(1),
   false = erlang:is_process_alive(Pid),
   {comment, []}.
 
@@ -83,7 +86,8 @@ info(_Config) ->
       ?MODULE, echo_fsm, {ok, state_one, []}, []),
   Pid ! {next_state, state_two, newstate},
   newstate = wpool_fsm_process:sync_send_all_state_event(?MODULE, state, 5000),
-  Pid ! {next_state, state_three, newstate, 0},
+  Pid ! {next_state, state_two, newstate, 0},
+  Pid ! {stop, normal, state},
   timer:sleep(1),
   false = erlang:is_process_alive(Pid),
 
@@ -96,9 +100,18 @@ async_states(_Config) ->
       ?MODULE, echo_fsm, {ok, state_one, []}, []),
   wpool_fsm_process:send_event(Pid, {next_state, state_two, newstate}),
   newstate = wpool_fsm_process:sync_send_all_state_event(?MODULE, state, 5000),
-  wpool_fsm_process:send_event(Pid, {next_state, state_one, newerstate, 0}),
+  wpool_fsm_process:send_event(Pid, {next_state, state_one, newerstate, 5000}),
+  wpool_fsm_process:send_all_state_event(Pid, {next_state, state_one
+                                              , newerstate, 5000}),
+  wpool_fsm_process:send_all_state_event(Pid, {stop, normal, state}),
   timer:sleep(1),
   false = erlang:is_process_alive(Pid),
+  {ok, Pid2} =
+    wpool_fsm_process:start_link(
+        ?MODULE, echo_fsm, {ok, state_one, []}, []),
+  wpool_fsm_process:send_event(Pid2, {stop, normal, state}),
+  timer:sleep(1),
+  false = erlang:is_process_alive(Pid2),
 
   {comment, []}.
 
@@ -107,14 +120,48 @@ sync_states(_Config) ->
   {ok, Pid} =
     wpool_fsm_process:start_link(
       ?MODULE, echo_fsm, {ok, state_one, []}, []),
+  ok1 =
+    wpool_fsm_process:sync_send_all_state_event(
+      Pid, {reply, ok1, state_one, newerstate, 5000}, 5000),
+  ok =
+    wpool_fsm_process:sync_send_all_state_event(
+      Pid, {next_state, state_one, newerstate, 5000}, 5000),
+  ok =
+    wpool_fsm_process:sync_send_all_state_event(
+      Pid, {next_state, state_one, newerstate}, 5000),
+  ok3 = wpool_fsm_process:sync_send_all_state_event(
+    Pid, {stop, normal, ok3, state}, 5000),
+  false = erlang:is_process_alive(Pid),
+  {ok, Pid2} =
+    wpool_fsm_process:start_link(
+      ?MODULE, echo_fsm, {ok, state_one, []}, []),
+  ok = wpool_fsm_process:sync_send_all_state_event(
+    Pid2, {stop, normal, state}, 5000),
+  false = erlang:is_process_alive(Pid2),
+  {ok, Pid3} =
+    wpool_fsm_process:start_link(
+      ?MODULE, echo_fsm, {ok, state_one, []}, []),
   ok1 =
     wpool_fsm_process:sync_send_event(
-      Pid, {reply, ok1, state_two, newstate}, 5000),
+      Pid3, {reply, ok1, state_two, newstate}, 5000),
   newstate = wpool_fsm_process:sync_send_all_state_event(?MODULE, state, 5000),
   ok2 =
     wpool_fsm_process:sync_send_event(
-      Pid, {reply, ok2, state_one, newerstate, 0}, 5000),
-  timer:sleep(1),
-  false = erlang:is_process_alive(Pid),
+      Pid3, {reply, ok2, state_one, newerstate, 5000}, 5000),
+
+  {comment, []}.
+
+-spec complete_coverage(config()) -> {comment, []}.
+complete_coverage(_Config) ->
+  ct:comment("Code Change"),
+  {ok, dispatch_state, State} =
+  wpool_fsm_process:init({complete_coverage, echo_fsm
+                              , {ok, state_one, []}, []}),
+  {ok, dispatch_state, _} = wpool_fsm_process:code_change("oldvsn"
+                              , dispatch_state, State
+                              , {ok, dispatch_state, []}),
+  {ok, dispatch_state, _} = wpool_fsm_process:code_change("oldvsn"
+                              , dispatch_state, State, bad),
+  [] = wpool_fsm_process:format_status(normal, [[], State]),
 
   {comment, []}.