decrease in calculated "range"?

What has your recent gas mileage been? It takes into consideration your recent gas mileage.

If you are only filling it to the first click, you are probably getting uneven fills too.

 

Agreed with xs650... Remember, the pump is a bit over-cautious on the fuelups that it will click off a bit early, maybe a gallon or gallon and a half early to prevent overflow.

 

Wait ... so what is the proper fill-up technique?

I have always only ever filled to the first click of the pump. I thought it would overflow if I tried to put in more.

 

I try to do it after the 2nd or 3rd click... You find that after the first click, it does fill in a bit more before it kicks off again.

 

I've always gone to the first click as everything I've read has suggested that for the vehicle, gas mileage and environment that's the way to go. But 2 or even 300's seems low, mine is usually around 450. I think it goes off of miles you got off the last tank, so once when I went past E and drove 500 on a tank and the next time it said the range was 500 (from what I understand after E there is still probably nearly 2 gallons left...1.9...)

 

Best time to fill up is early morning (you get more fuel for your dollar) and use the slowest automatic setting on the filler. It takes a few extra minutes, but it is worth the time.

 

Why? Do underground fuel tanks in your neighborhood cool measurably overnight?

 

The temperature of the underground tanks are fairly consistent, but the 2-3 gallons in the pump itself can vary quite a lot (up to 20-degrees on hot days). When I am only filling up 8-9 gallons that can make a difference over time. Also, the fuel remaining in the car's tank has expanded throughout the day leaving less room to fully fill the tank.

 

The only way you have 2 or 3 gallons of gas in your pump is if you have one of these old gravity pumps

 

The pumps I use are sufficiently busy that the pint or so held above ground won't warm much in the few seconds to minutes since the previous customer left.

This is an argument for filling in the afternoon, when the fuel already in your tank is at its hottest and most expanded, allowing less room for more fuel. This reduces the possibly of the new fuel expanding enough to overflow and spill.

Dad had a habit of absentmindedly overfilling the tractors in the cool of the morning, despite my protestations to please stop before it reaches the top. That left me watching the fuel tank, virtually in my lap, overflow most of the morning as the expansion in the hot sun, combined with sloshing over the bumps, squirted fuel out the vent hole almost all morning. Only near lunchtime did the fuel consumption drop the tank level enough to stop squirting out.

Then I'd drive back to the house in a pickup that had warm fuel dribbling out the filler cap because its cold fuel had expanded, and the truck had been parked on a sidehill with the fuel cap on the downhill side.