When your clothes dryer says “check vent” you really should. In this case the outside vent cap was unobstructed. But the dryer insisted. I pulled the dryer away from the wall to disconnect the flex duct and discovered it packed with straw – apparently by a bird that thought it would make a cozy nest.
I pulled out a giant wad of grass, cleaned the flex duct, reconnected it, and thought that was the end of the matter. “Check vent” came on again. This time I reached deep into the vent on the dryer side and pulled out another foot-long plug of woven grass!