I recently began to notice a gurgling sound in one side of my double kitchen sink whenever water is sent down the drain on either side. The water drains normally so I don't think the drain is plugged. I do think that the vent pipe might be plugged but am not sure how to clear it.
Here's what I know: About 15 inches below the top of the vent pipe there is a "floor" with an off-center hole about 1.5 inches in diameter. About 3 feet below that there is something that feels solid. Using a shop vac I was able to remove a very small amount of what appears to be decayed vegetable matter (leaves, etc. I suppose). Probing, it continues to feel solid.
Dare I poke hard at this "plug" trying to open it, or is there a screen at that level that I should be careful to preserve?
The house is about 50 years old. I've lived in it for 40 years without experiencing this issue until recently.