diesel man 03 wrote:
If the tank was full the P trap would be full also, line plugged some place, my 2 cents.
He didn't specifically say that there was standing water in the sink (including water in the p-trap), but, he wouldn't be asking about a plugged sink line if there wasn't standing water at one time? If the line drained, he wouldn't be complaining it was plugged... It could, in fact be draining, but, draining slowly, which could, aside from a clog down the line somewhere, indicate a tank almost at its maximum capacity. At any rate, the p-trap
should be full...that's how they work; they stay full of water to prevent the back-flow of sewer gasses (methane, besides stinking is poisonous). If your p-trap isn't full, you've got a siphoning/venting issue and that is a problem in itself.