I'm sure this is a common problem but I need some advice on the best way to unclog this thing. The kitchen sink suddenly started draining extremely slow. I tried 2 of the liquid unclogging products and no help. I used a small Rigid snake and went in from under the sink where the pipe goes into the wall and I think the snake went up the vent because it didn't unclog a thing and it sounded like it went up. So I went downstairs to the drain clean-out and ran the snake up. The snake seems to just want to twist up and not move forward because the pipe is 1-1/2" or 2" and the snake just twists.
I saw an answer from "Speedball1" about snaking the roof vent. Is this what you think I need to do as well? Any other suggestions?