yes app pool is running ( i used to restart it after every crush)
yes, there is more info in %systemroot%\system32\logfiles/HTTPERR :
2017-10-23 09:59:08 ip 52798 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 09:59:10 ip 52799 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 09:59:10 ip 52800 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 09:59:11 ip 52801 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 09:59:11 ip 52802 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 09:59:11 ip 52803 id 9900 HTTP/1.1 GET myScript.pl 503 14 A
+ppOffline MyAppPool
2017-10-23 10:01:12 ip 51689 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 10:32:36 ip 52745 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 10:35:06 ip 55205 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 11:07:29 ip 52830 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 11:25:31 ip 51432 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 11:33:22 ip 51495 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 11:43:47 ip 52070 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 11:47:19 ip 53275 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 11:47:19 ip 53276 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 11:47:20 ip 53277 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 11:47:20 ip 53278 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 11:47:21 ip 53279 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 11:47:21 ip 53280 id 9900 HTTP/1.1 GET myScript.pl 503 14 A
+ppOffline MyAppPool
2017-10-23 11:59:19 ip 53329 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 12:11:45 ip 52854 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 12:33:22 ip 53659 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:33:22 ip 53660 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:33:23 ip 53661 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:33:23 ip 53662 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:33:24 ip 53663 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:33:24 ip 53664 id 9900 HTTP/1.1 GET myScript.pl 503 14 A
+ppOffline MyAppPool
2017-10-23 12:37:38 ip 53712 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:37:38 ip 53713 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:37:39 ip 53714 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:37:39 ip 53715 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:37:40 ip 53716 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 12:37:40 ip 53717 id 9900 HTTP/1.1 GET myScript.pl 503 14 A
+ppOffline MyAppPool
2017-10-23 12:41:53 ip 51633 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 12:55:44 ip 54313 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 12:55:59 ip 51757 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 12:59:04 ip 51708 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 13:01:55 ip 51742 id 80 - - - - - Timer_ConnectionIdle -
2017-10-23 13:07:54 ip 53920 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 13:07:54 ip 53921 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 13:07:55 ip 53922 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 13:07:55 ip 53923 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 13:07:56 ip 53924 id 9900 HTTP/1.1 GET myScript.pl - 14 Con
+nection_Abandoned_By_ReqQueue MyAppPool
2017-10-23 13:07:56 ip 53925 id 9900 HTTP/1.1 GET myScript.pl 503 14 A
+ppOffline MyAppPool
2017-10-23 13:11:10 ip 51874 id 80 - - - - - Timer_ConnectionIdle -