At least in Poland the petrol stations are certified on regular basis and can't have more than 0.5% error. So calculating it from petrol stations is actually a good idea. Even if those are not perfect and your car has constant 10% error I would like to have it closer to what I pay for than what it really uses.
They are in the US too, meaning the amount the pump says you pumped is accurate.
All valid points. That's exactly why, when I'm around home, I try to fill up at the same station and pump as much as I can. Even doing that, the difference between what the computer said I got and what my manual calculations said were on average between 1.2 and 1.5 mpg off. It was pretty consistent. I took a 3500 mile road trip August of last year and those numbers stayed relatively consistent without filling up at the same station twice, but I had one tank that was almost 2 mpg different and one tank that was only 0.8 mpg off. Since I've made the adjustments on my car, I've averaged 0.2 mpg difference between the computer and my calculations with a maximum difference of 0.4 mpg and a couple of tanks that were spot on. That tells me fuel pumps aren't that far off.
I use "Fuelio" app to track every single fill up. If you track fill up for longer time, than inconstancy doesn't matter. If you have 1 fill up, then inconsistency of 1 fill up matters. If you have 50 fill ups, only the inconsistency of last one has any impact on your calculations. And because you have 50 fillups, then that inconsistency importance drops to 1/50 of what it was.
I'd say Ford is generous in their calculations to make you feel better. It's the same on my 2020 Bullitt.
Yes. 2020 GT PP1 manual. I kept track of the miles, gallons and displayed MPG for at least 1000 miles, then calculated my own figure. The car's number was higher than mine, so I lowered the number in Test Mode. Drove another thousand miles and fine-tuned the number again. It's very close to accurate now, but I'm tracking it one more time to see if I can make it even better. When you say you haven't had any luck, what part of the process is the issue for you? (Please don't let it be metric vs. SAE, or whatever our 'Merican measures are called.)
As I recall, I can't get it to set at the adjusted value. In other words, I'll adjust the 1.000 to .980 or whatever and it won't set at that .980.
Thank you!!
Maybe click "okay" after adjusting. It's been a couple years but I think I ran into the same problem. I've got my Mustang and F-150 both to where they're pretty spot on. I've kept spreadsheets for both so I can keep track of everything, including the afe bias number.
I don't think the car does know how much has been injected. It just knows how much would have been injected if every part in the path exactly matched the target specs for those parts. I suspect the procedure lets you adjust for however off your combination of parts is from perfect.