I just spotted diesel fuel flowing from my overflow hose while parked. Sure enough, when I cracked the fuel cap diesel was overflowing. It was not overflowing earlier when I parked it. The tank was just filled days ago and it has not been driven.

By chance, this car also stalled on the highway days ago. I thought it was a clogged filter and maybe fungus (I have two 300Ds with fuel issues, so this is not a repost). Waiting for defung enzyme and new filters.

Could they be related? Tank vent problem? Can this really just start happening from thermal expansion? It's sunny and 80 degrees or so.

It's an 85 300Dt.