Calibrating the UltraGauge...
 

So I decided that I’m tired of my UG throwing our trip averages that are clearly at least 20% optimistic, so I decided to fully reset it and begin anew, since I couldn’t just roll back the 70k miles that I’ve driven with an UG connected...

For some reason it had my car making 220lb/ft of torque... reset that to 150...
reset engine size to 2.2liter, tank size to 12 gal... set injector cutoff?

Gauge says go >7x engine size... I set it at 15, guessing at the figure... NOPE! Registers cutoff coasting at idle... set it to 16? Makes gauge less super sensitive but still too sensitive, registers cutoff as engine speed drops as I take car out of gear, before i kill the ignition.. set to 17? Shows DFCO as I engage it, shows fuel consumption as engine drops to idle, BUT... as I bump start the engine after a coast, it doesn’t register that I’m burning fuel until after I put the car back in gear, and if I just restart the engine and go back to neutral, instant MPG stays at 999.9 until I rev the engine, then it goes back to normal... I turned DFCO detection off for now, don’t want averages even more optimistic than before...

I still think my UG calibration issues stem from maybe bad O2 sensors(that aren’t throwing codes?), but I did my first calibration last night... corrected the distance up around 6% from what the UG had, and corrected the fuel used, up by like 16%... it corrected the average the UG had for the tank to the 50.36mpg I actually got, and now it seems better...

First thing I noticed was lower instant readings when accelerating... with IAT around 80F, instead of 5th gear accel being at around 20mpg instant, it’s now more like 17-18... my trip home from Flatwoods that went really smoothly and with no forced braking, that would have showed around 70-72mpg avg, now showed like 63...

I *did* friggin nail the first leg of the trip home, averaging almost 100mpg over the approx 6mi though...

Nice work! I've never really been able to nail the calibration in my Civic either. You seemed to go a way different route to calibrating it than I did. I've never gotten mine to see DFCO and it messes with my numbers a bit depending how much DFCO I actually end up using.

Oh, my UG would see DFCO all right, it would see it whenever I was idling... I ended up turning it off and am dealing with it not zeroing our my fuel usage when I EOC

has been 7.5 years since i got my UG. I hardly remember calibration anymore, but it gives me mostly accurate distance and fuel readings. Fuel is usually off by a percent, maybe two sometimes. I have had it showing DFCO for four years maybe. All good. I think u just play with it til it gives up confirmable numbers.

I’ve had my UG on a verbal different vehicles from the Suzuki Forenza I started with, to the Saturn Ion I’m driving now... it was never really re-calibrated for each car, just plugged in and basic values set... I’m still blaming my O2 sensors for the UG not always picking up EOC, because the UG will show weird values for DFCO if I set it to show... right now it’s disabled until I can change my sensors and I’ll likely recalibrate then too...

Hmm, maybe I'll quit complaining. It's usually down to about 1-2mpg variance, so about 2% and change to 5%. I was too used to how airtight my calibration was in the Echo, consistently under .5mpg variance!

My UG had been showing figured that I estimated were 15-20% off before I recalibrated...