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It's virtually impossible for a 37% (50-36.5)/36.5 increase in tire pressure to account for a 29% (45-35)/35 FE increase in fuel economy unless perhaps you were creeping along at less than 10 mph.? But there is no question that increasing the psi from around 36-37 to around 50 psi will improve fuel economy. For example, the change in rolling resistance (RR) due to a tire pressure change would be a small part of the drag of a car at normal driving speeds. Below is a chart of the road load HP of the 2013 C-Max (I don't feel like looking up the 2016 / 2017 data but it will be very similar if it was changed at all) at various speeds based on the data which Ford submitted to the EPA. The decrease in RR by increasing tire pressure is less than the percent change in pressure. Again, I don't feel like looking up the numbers from studies and tests but for the range we are talking about, I would say that a 37% increase in psi might be as high as a 25% decrease in RR. So, applying the 25% reduction in RR to the blue bars the chart below, one can see that if ones speed were 30 mph, one would expect RLHP to decrease by 12.5% (50% * 25%). Assuming this decrease in RLHP results in a 1:1 increase in fuel economy. Once might expect the 35 mpg to go up by 12.5% or up to 39 mpg if driving at 30 mph. Now at 50 mph speed, the 35 mpg would only go up about 7.4 % to 37.6 mpg. (See my post below for lowering the 25% reduction in RR to more appropriate levels). Also, one must note that the RLHP coefficients used by the EPA are based on coast down data and rolling resistance may affect a small portion of the red bars. The green bars represent aerodynamic drag. In addition, if you have mods that decrease aerodynamic drag by say 10%, the green bars would be lower by 10 % and the effect of increasing tire pressure on fuel economy would be greater as the blue bar % would increase.

You need to program them. Roll the window down, then hold the switch in the full up position. When the window reaches the top, continue to hold the switch for 3 to 5 seconds after it's closed. This will set the limiter control and activate the auto up function. Do this for all windows that aren't auto closing.