Ultra-gauge
 

Having some instrumentation that works is great. The onboard computer is pretty optimistic in comparison. Makes you wonder how many people ACTUALLY trust the onboard gauge.

Makes you wonder how many use it and if it changes their driving style.

...that's the problem I'm having with noobies over on the CruzeTalk website--they're all "believing" the numbers from the Drivers Information Center (DIC...how appropriately named?!?!) rather than first verifying those numbers against a "one-click" tank-fillup.

...by the numbers I'm tracking on the wife's Cruze, the ECU is consistently under calculating the fuel consumption GALS by a rather consistent 5-10%, which means all the DIC dispaly MPG values are likewise 5-10% too optimistic.

This tank was the second with the UG and it reported 37.3 and actual was 37.33 mpg.
Awesome!

...both the SG and UG, once calibrated, seem to give far more accurate results than just about any of the OEM built-in dashboard display units...at least that's been my experience.

...FYI, even though you've calibrated the unit now, be aware that when the gas companies switch over from "winter" blend to "summer" blend, the meter accuracy will likely change...and it'll change whenever they change the amount of ethanol alcohol in the blend, such as from the current 10% (E10) to the new EPA limit of 15% (E15).

I will also confirm a recalibration for winter mix. I had to adjust my UG for my Subaru at the end of December, it seems to be slightly optimistic, but thats okay. Even in an over-calibrated situation, I can still tell I'm doing good or bad for the tank.

I also have issues with my Subaru for extreme colds (PA extremes lol). My mileage always dips if we're down near zero or below. The Subaru runs extremely rich when cold, so the UG will be off for me.

Is there a simple way to calibrate the ultragauge? Similar to how the scangauge is calibrated?

UltraGauge instructions.
 

Never had a scangauge but here is an excerpt from the ultragauge manual.

Calibrate MPG/Fuel
MENU  Vehicle Setup ..  Calibration..  Calibrate MPG/Fuel
This calibration is used to fine-tune UltraGauge to accurately measure fuel usage. This calibration is critical, especially for vehicles
which use a MAP sensor, diesels and alternative fuels.
 For vehicles that use a MAP sensor*, see the menu section on Adaptive Volumetric Efficiency before proceeding.
 Prior to this calibration, consider performing the distance calibration. See the section: Calibrate Distance
The gauges that depend on fuel usage will not be accurate until this calibration is complete. To perform calibration, please follow
these steps.
1. Fill up the fuel tank. Once filled, press and hold the UP key to cause UltraGauge to recognize the fill-up
Zero the Average MPG. MENU  Gauges  Zero Ave MPG, G/H.
2.
At the next fuel fill-up, note the number of gallons used (pumped). Select MENU  Vehicle Setup..  Calibration.. 
3.
Calibrate MPG/Fuel and enter the fuel used. Press MENU when complete to set and save the calibration. Use the same
Gas station and pump for best results. Alternatively, record and add the actually gallons used over several fill-ups to
improve accuracy.
4. The Calibration factor will be displayed at the bottom of the screen.
Congratulations, you have successfully calibrated UltraGauge to your vehicle.
Make note of the calibration factor. If you should ever need to clear your configuration, the calibration factor can be used directly
to set the calibration. Simply jump to step #5 and increase or decrease the reported gallons until the calibration factor matches.
* To determine if your vehicle has a MAF sensor, access the menu; MENU  UltraGauge Setup..  Version. This will display
MPG sensor: MAP, MAF or None


Manual may be downloaded here:
UltraGauge Support

I advise reading and understanding the set up instructions first and then not plugging up the UG until filling up. You can then keep tabs on calibration as you go through the tank.
On my first tank I checked calibration after each 100 miles and then upon filling up again the UG reported I used 16.112 gallons and I actually used 16.351. The second tank needed no touch up on the distance calibration and the fuel reported use was spot on.

The fuel use report since first installing is a running tally...
First tank report was 16.112 (calibration tank) actual was 16.351
Second tank report was 31.659 which is the first tank of 16.351 and the second tank of 15.308. It was dead on accurate of the amount of fuel used.

Bharvey how long from when you ordered you ultragauage did you get it?

I received mine in 2 or 3 business days, IIRC.

I ordered mine during there shut down so it took a couple of weeks.

I ordered mine on 11 Feb and received on 16 Feb.

I ordered a second one today, loving my first one compared to the scan gauge 2 (sorry). To bad they are back ordered. But I suspect the price will hike yet again by the sudden surge in popularity so I ordered it anyways rather than wait.

I've got mine in the car - not calibrated yet. Still annoyed at their 30day limit on the $9 rebate. it took me more that than to get around to filling out their form (three tries to get all the info!).

I'm updating my post to reflect that it appears they have honored their rebate, despite my submissions being a few days beyond their 30 day window. Now, just gotta figure out how to calibrate it.....

Old Tele man -

Yeah, even though they have access to the fuel-injector pulse-widths ala the MPGuino, I wonder if they are just using a (rose-shaded) algorithm as well.

CarloSW2

Do any of you have issues with the ultra-gauge missing a few of your miles? I've got mine calibrated, but occasionally it will vary off of my odometer by up to 1%.

I think the reason why is because I typically start my truck, immediately put it in gear, and get moving. I suspect it is "missing" a few clicks before it is totally booted up.

Other than that, I've got good accuracy on mine. I just filled up this morning with 30.7 gallons and it was reporting 30.7 used 18.85 actual mpg vs 18.9 reported.

UG has a mileage calibration. :-) How new/old are you tires? a few fractions of an inch can cause a variation in the mileage from speedo cable an the mileage off of a electric impulse.

I have it calibrated for mileage...

This last tank was off by less than a mile. The tank before, it was off by about 6 miles. The tank before was right on. If it was consistent, I could tune it out.

Differences in the tire due to wear over time will cause a deviation on the odomoter reading... but my dash and my UG will both have the same deviation as both are collecting data from the same signal.

Whatever the reason, it's only a small difference and doesn't affect the usefulness of the data.

New tires at 44 psi= 1.0265 difference in odo vs gps.
20,000 mile tires at 50 psi= 1.0285 difference in odo vs gps.

My UG has read anywhere from .7 low to .7 high.
If it was consistently high/low I could then adjust the VE RPM value.

My onboard dash gauge reads from 1 to 4 mpg high and always high.

Both UG and SG lose distance when rolling with the key in off position. If I drive my test loop with cruise control, the UG/SG show I've traveled 9.9 miles. If I drive the same loop with P&G, they show the distance as 9.6 miles.

That's not it for me. I've got an auto and don't feel comfortable EOC, I just coast in neutral, engine on.

Most automatics are not flat-towable, and should only coast in neutral, engine on.