Inspector 1, I'm wondering ... Where does that extra fuel go?
I remember early 1970s GM cars had charcoal cannisters that would get saturated with fuel vapors. Can the extra vapors richen the mixture somehow and waste fuel?

I take it, that it's better to just fill up until the gas pump shuts itself off THE FIRST TIME when refueling? In other words, don't try to squeeze in another gallon or so.

I know in NJ (full serve only) they will top it off to the next higher dollar amount.

Tonight I filled my 300TE and got 19.5 mpg, not topping it off. I had been getting 17 mpg. I'll track this over several tankfuls to see if it's a statistical fluke. If my mileage improves, I'd rather pay $20 than $25 any day

Thanks, Bob

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Bob Roe
Lehigh Valley PA USA
1973 Olds 88, 1972 MB 280SE, 1978 Datsun 280Z, 1971 Ford T-Bird, 1972 Olds 88, 1983 Nissan Sentra, 1985 Sentra, 1973 230.6, 1990 Acura Integra, 1991 Volvo 940GLE wagon, 1983 300SD, 1984 300SD, 1995 Subaru Legacy L wagon, 2002 Mountaineer, 1991 300TE wagon, 2008 Murano, 2007 R320CDI 4Matic 52K, some Hyundai, 2008 BMW 535xi wagon, all gone... currently
2007 Honda Odyssey Touring, 2014 E350 4matic