We have had strange faeces in our garden for about 2 years that we are unable to identify. It appears overnight, always in a border. It is about 5ins in dia and in a coil. It is always the same colour and consistency, smooth and pale brown. It has a fairly large hole beside it and is always uncovered, quite smelly too!!! We dont have any badgers in the area and there are no signs of digging elsewhere either. I have a photo of it which I could email to anyone who thinks they can help.
Got to agree with kira000. It's almost certainly a domestic dog (too big for a cat). Dogs generally make a half-hearted go of covering their faeces but it's usually no more than a scrape or scratch (which may also have a function as scent marking). The consistency of 'consistency' and colour also indicates a dog that is probably fed the same thing day after day. You'll have to catch it in the act then complain to the owner. Good luck.