'Funk'. Oh dear.
Inventive psuedo-swear words can be great, in context. (Dan Abnett's particularly good at making them up) But, generally, if you want your characters to swear, then let them swear properly. If you don't, then forget about it, particularly if you're going for grim'n'gritty in your story.
I really liked the first episode of Savage, but all that 'funk' and 'funking' stuff was a big unintentional comedy put-off.