Upstairs sink won't drain despite snacking and clean trap
My upstairs bathroom vanity sink is giving me problems. When it wouldn't drain, I took apart the trap (PVC accordion on sink end), cleaned it and the sink drain, and snaked in as far (not real far) as I could go into the drainpipe. After I reassembled everything, the sink was worse then before, with water backing up the trap and leaking out through the slip nut on the sink tail piece end. The local hardware store suggested I may have an air vent problem or a clog further down the drainpipe. I'm trying an enzyme based clog remover but still not remedied. Any suggestions?