Well I got it to work twice tonight.....

....but not all the time.....

.....Both times the Siren worked...it was Critical Hit.....I think Dowly is right....if the "Oil is Hit" you get the sound.....
I'm still messing around with the Sound useing Timetraveller's Mini Tweaker....(Thanks Reece) for pointing me in the right Direction....
The 2 times it worked it Sounded GREAT!
The other times.......

well not so good....

Still working on it....if anyone wants to help please pm me and I'll send you the File....