Originally Posted by
talaniman
It is sounds like the toilet in question has a partial blockage(?) close to the source (Before it intersects with the main, or other common drain points). Have you tried the plunger and flush with water using a bucket? That's where I start as the easiest thing to do. A 10 foot snake through the toilet itself, or removing the toilet and snaking the drain directly is the next move.
Where is the toilet in relationship to the other draining appliances, and toilets/sinks? A bit more info please, since a backup/overflow indicates a close to the toilet blockage not a "bad toilet".