Man, when my account is not active, one of the most annoying things I have to deal with is staying UNDER the 1000g cap. Hell, I have to resort to purchasing large quantities of stackable vendor items to horde until the next time I am active and can vendor them and stash the gold in my warbank just to be able to keep looting things.
I can 1000g cap myself in less than an hour just looting greys from the Tuskar Tacklebox's and scout's packs in DF zones. Hell, a single 20 stack of the some of the greys from the Tuskar boxes are close to 1000g themselves, and some are close to 2000g per 20 stack. You need to be renown 27 or something to unlock the tackleboxes, but its super EZ gold if you do have it.
If you have a twink with spamable AOE like druid, monk, or warrior, you can use the dragonkin hyperspawn in the wetlands, there is an area between the Wetlands and Twilight highlands where those 4 legged dragonkin are fighting orcs, and they spawn very fast. Just sit in one spot with your AOE button held down and loot every few minutes.
You can also use the "Kings Gambit" quest in Zul'Dazar if you are Horde (just don't talk to Rastakhan once you start the quest, the mobs endlessly spawn and drop greens/greys/raw gold). If you haven't quested in Zul'Dazar at all, it takes maybe an hour to progress to that point, but once you do, you can just never complete that quest and use it to farm greens. Just abandon and restart as needed.
Aside from that, just playing the game like normal, or running dungeons should cap your gold pretty quick.
What is your biggest gold sink? How are you even burning through the gold you do make before you hit cap?