My kitchen sink won't drain. It takes like a day to drain. We had a new dishwasher installed a few years ago and the sink has had problems ever since. We have a under the sink vent but doesn't help. The other sinks in the house work fine. The drains have been snaked but not the vent. There is only one vent and it's on the other side of the house near the bathrooms. The kitchen is on the opposite side of the house.

Kitchen drain is the dirtiest drain in the whole house. New dishwasher should not be the culprit. It only magnifies the problem. Most likely, your kitchen drain needs cleaning. Remove trap and clean drain with 3/8" x 25' snake. Snake it several times. You can rent snake in Home Depot for few bucks. Or call drain cleaning company to do the job for you.