Kitchen sink drains slowly. It has a sure vent on drain. Is the slow draining related to possibly a faulty sure vent?

While very rare, it is possible for a mechanical vent to fail.

I would suggest you remove it to see if the sink drains any faster, but I don't want to create a situation where the drain backs up through the removed drain and floods the sink compartment.

Maybe you could have a second person hold a dishrag over the opening while the sink is draining, just in case it does overflow.

Plumbing code requires that the mechanical vent be at least 6 inches above the trap, but I try to hold them up as high as possible inside the sink compartment, so that removing them with a sink full of water doesn't flood the sink compartment.

Kitchen sink drains slowly. It has a sure vent on drain. Is the slow draining related to possibly a faulty sure vent?

Hey Tony

Growler gave you good advice on how to test your vent. If the sink starts to back up through the vent then you have a blockage in the lateral,( the horozontal line in the wall). If that's the case then remove the "J" bend from the trap and send a snake up the pipe in to the wall. You'll run into a elbo about 6" in but once past that you only need to put out about 6' more.
After snaking the line flush it out with a couple of tubs full of hot water. Good luck, Tom