one more symptom
after a long time with the noise not recurring, it started up again this evening during a drive.
on a hunch, after I'd noticed that I was below half a tank of gas, I went to the local gas station (humming sound quite evident) and filled up the gas tank.
driving home, no humming noise at all!
I wonder what condition, when the tank is below half full, that causes that humming noise....it appears to be quite a piece of work to get to the check valve on the gas tank too....
so maybe I'll top her off when she's at half tank from now on.....
Network Integration Engineer
MCSE, CLP, CCNA