Ultragauge: Do I need to reset AVG mpg at every fill up?

[sviking]

Well, I calibrated my Ultragauge over four tanks of fuel and the fifth tank was pretty spot on. Within .5 mpg of what the unit reported. Excellent! Now, as the title said, my question is:

Do I need to reset the AVG miles/gallon every time in addition to holding the top button to get the Ultragauge to recognize the fill up? I didn't do it when I filled up yesterday and the AVG mpg is holding steady and hasn't changed even a tenth of a mpg, which seems strange. Thanks!

[bestclimb]

no You don't have to reset the avg, however if you do not the average mileage will include the mileage and fuel from the last time you reset it. This will skew the DTE. If for example you drive all summer at 30mpg, then winter hits and your mileage drops to the 25mpg range. The DTE estimate will optimistic.

[frv]

I always zero the Average MPG and gallons per hour when i fill the tank.

I go into: Menu, Gauges, Zero Avg MPG, G/H.

I use Oil Distance for my tank distance and reset this on fill up too:

Menu, Gauges, Zero Oil Distance

After every trip and tank fill up, I record all the info I'm interested in and reset the trip gauges and run time gauge:

Menu, Gauges, Zero All Trip.

Menu, Gauges, Zero Run Time.

After that I hold top button to tell UG tank is full.

Sounds like a lot of messing about but I only fill my tank about 10 times a year and it doesn't take long!

The UltraGauge is agreat tool to help improve fuel economy. I've had mine over 2 years now.