Yes, it measures EOC properly. There's no fuel consumed, and the miles keep being counted. At the end of my 9.6 mile test loop, P&G mpg results are the same with the UG as they are with the SG. Distance results are the same, too, with only 9.3 miles measured. The UG loses miles duing the key-off time, just like the SG.
I took delivery of my Ultragauge Saturday. so far it apears to do exactly the same stuff the Scangauge did but at a price that is much more palatable to the average consumer. The main things I like are the size (it's tiny) and the display (for it's tiny size the display is huge and well laid out). I have only put a few miles on it and I like it better than the scangauge. The main reason is it blends with the interior better than the scangauge second is it's easier to read.
I mailed in my rebate paperwork today, and noted that exceeding 170 degrees internal temperature on the UG voids the warranty. When I left it in my xB's window on a 100 degree day, the internal temp went up to at least 173 degrees, so be forewarned. Rather than unplug the UG, I remove it from its mounting stalk, and stow it out of sight under the dash and out of the sun, now. It looks a lot like a small GPS, so you wouldn't want to leave it in plain sight anyway. Someone is sure to break your window and try to steal it.
Clarification on the introductory $39.95 price. I should have said that's plus ~$8 shipping, and after a $9 rebate. So I was billed about $56, and will pay about $47. Now that regular pricing applies, an UltraGauge will cost about $68 - about $100 less than a ScanGauge.
This may be a dumb question, but I'm just getting started here. Bought a 94 Civic VX a few weeks ago. Does the UG only work on OBDII cars? What about the SG?
Also, are you getting that 46mpg average simply through driving habits, or have you done any mods to your Scion?
there is the mpguino that you can use on older cars though I know very little about it since I have obd2. several people have used it and it seems to be fairly nicely done but I think it is a kit you have to build yourslef.
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