Why do I get sewer smell I'm my bathroom (seems to come from sink area) when my washer goes into the final spin? I have run water to make sure the trap is full.

I get sewer smell I'm my bathroom (seems to come from sink area) when my washer goes into the final spin. Here's my take on this. You have a partial blockage in the washer drain line that allows a tub or lavatory to drain with no problems. However, when the washer discharges it does so with great volume and pressure. The discharge hits the partial clog and momentarily bounces back , before it drains past, sending a bubble of sewer gas back up the line past your lavatory trap. The solution would be to snake the washer drain line. Good luck, Tom

My take on it: Could be that your washer drain is not vented siphoning your sink trap. Your sink drain may not have a vent either...