Hi guys,
I have water leaking from my exhaust at the seal in between the cat and resi, had the exhaust off the other day so i'm guessing i just have to tighten that up but my question is what causes water to leak out of the exhaust?

How much water? A few drips in the mornings or drips after a drive?

If it's only a few drips in the mornings, it may just be condensation within the exhaust system. A fair bit of condensation would be occurring especially with current Melbourne weather so more water than usual would condensate once you start the car up in the morning.

When you took your exhaust off, did you put a new gasket between the flanges? If not then tightening might not seal it up properly, best to get a new matching gasket.

Yes i did renew the gasket, I think it may be just condensation, thanks. . If it was leaking more, do you know what would cause this to happen?