2016 Malibu Hybrid fill up
 

I find it impossible to track fuel mileage with this car. I try to consistently stop filling after two clicks of the pump, but get different tank levels. As a result the calculated and computer indicated mileage is not comparable. My last fill up indicated 35.7 on the dash readout, but calculated 48.04. There is no consistent way to fill this tank without overfilling to the point of seeing gas coming out. Any thoughts?

There will no doubt be differences in pumps too. I always wait for two clicks, then gently squeeze the trigger whilst suspending the nozzle just above the hole so you can see the fuel entering. Then you can stop when the fuel stops going down. Yes I know fuel expands when warm, and you shouldn't do it, but it's the only way in my opinion to be consistent and get accurate figures. It can be quite time consuming too, adding a further 3 minutes or so onto your filling time.

If possible, use the same station, pump, and stop filling at the same point. Besides filling until you see fuel in the filler neck, this is about all we can do without breaking out scales or graduated cylinders.

Try to use the same station, same pump, and pull up to the pump facing the same direction. Personally, I fill and stop at the first click. It also helps to wait until you have 1/4 tank or less before a fillup. These variances are more easily absorbed/negated the more miles you have on the tank. Also, if you're consistent, you may have small variances on a tank by tank basis, but that all evens out when you look at your overall average.