The phrases "mettere il pepe al culo a qualcuno" (literally: put pepper in someone's *** -- light a fire under s/o), "avere il pepe al culo" (to have pepper in your *** - can't sit still, ants in your pants), or "correre come uno con il pepe al culo" (run like somebody with pepper in his *** ... whose *** is on fire, i.e.) all exist in Italian, along with other variations on the same theme, so I can confirm that the meaning of your saying is along those lines (though "Pepper up your ***" doesn't mean much without knowing how it was used -- e.g., meaning, "get your *** in gear?"). That said, "culo se pepe" or something close may well exist.
"Culo se pepe" isn't Italian, though. It could certainly be Sicilian dialect -- the relevant words would appear to be "pipi" and "culu," in that case, though I can't find them in any combination that resembles your example. You'll need to hold on until a reader who knows Sicilian comes along! In the meantime, I'm putting into the sources a list of Sicilian sayings w/Italian translations.
never heard it. definitely isn't standard Italian, might exist in SicilianItalian to English translation: Culo se pepe.....?
also in sicily we say
avere il pepe al c u l o
Culo se pepe isn't sicilian
It's used "hai il pepe in culo" (you have pepper in ***) or "hai un razzo in culo" (you have a rocket in ***) when someone seems to moove too fast or to walk too fast.
"Culo se pepe" doesnt make sentence, probably he used to say "Pepe su culo"Italian to English translation: Culo se pepe.....?
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