Yes, but there are other factors.
For example, I have recorded a significant MPG difference (2MPG) between cold weather (30s-40s) and warm weather (60-70) driving.

So, some people might be observing an increase in MPG due to warmer weather. Also, places should be getting away from winter fuel blends (10% alcohol here in OR), this should also increase milage.

 

Mchines are not suseptible to the placebo effect but machines do not post such comments here either, the drivers do and they are very much suseptible to the placebo effect.

Also keep in mind the EPA mileage ratings are based a fixed procedure and is used for "comparison purposes" only, they are in no way a defenitive number for true gas consumption of a car.

 

True, except that here in MA the weather has not changed much since the middle of February. With exception of two warm days it has been in the 30s and 40s. And we are probably still using winter gas. I will check for further improvement when it gets warmer.
I am pretty confident about attributing the improvement to the re-flash, especially considering that the new fuel map is leaner.

 

I know that EPA uses an odd indirect procedure and the number is not supposed to be a precise measure of true gas consumption. However for the vast majority of the cars EPA’s numbers turn out to be close enough to the actual consumption so that consumers reasonably use them as an estimate.
It is possible that because of the 8’s unique design EPA numbers are so wildly different form the actual mpg. In that case Mazda should have disclosed this fact.

 

Ok...just got L flash on my car yesterday....seems rougher when cold but smoother and better with a slight increase in power...or so it seems. Gas mileage is yet to be determined. What is the 20 pump brake test? Do I need to do that? Help out and inform this young lady!!!

 

Over the course of ownership (8 months now) I have tried every strategy for improving mileage: different octanes, driving styles, shift points, fuel brands, etc etc. No matter what I do, I get 16.8 mpg. Sole exception is long road trips (freeway) where I get about 20 mpg.

This makes me think mileage is a function of two factors almost exclusively. One is, how much freeway driving you do. The other deals with when/how your car was made. These two factors alone explain the variations among us, and there is a good thread on statistical analysis that backs this up (with data collection from many owners.)

I just got the L update. I will start tracking mileage. If I get anything other than 16.8 i will attribute it to the reflash, since my ratio of freeway driving is not going to change.

 

The 20 pump brake erases the "keep alive memory" in the car, and allows it to start fresh learning your driving habits. With the "L" flash, you can verify that you have successfully completed the procedure by watching the oil needle "sweep" just past halfway and then back to the left again.

I reset mine before every autocross - if nothing else, it freaks out the competition - they think I'm nuts..........

 

I've been flashed twice....no mileage improvements....but it wasn't bad to start with. Still between 17 and 19 city/highway mix and 20 to 23 all highway. Forget about improving the gas mileage and JUST ENJOY THE RIDE. Otherwise trade it in on a Honda Insight or Toyota Prius.

 

Thanks tpryor...I did not know that...ok...will try it.

 

It's easy to say "Forget about improving the gas" when you're getting up to 23 mpg. For those down in the low teens, we'd like to get where you are and THEN forget about it. btw, if you want to forget about it and just enjoy the ride, how do you know your mileage before/after flash, on/off hiway; sounds like you're monitoring it pretty close.