What is the average Scangauge II offset percentage ?

[127.0.0.1]

Hi,

I am going to be moving my Scangauge II from my 4runner to the new Yaris.


I wish to program it right away with the percentage offset so it accurately measures MPG from the first fillup.

What are you guys usually getting for an offset ? My 4runner is 4.6-5.2 %.

When I setup the Scangauge for the Yaris, what % is the most common ?


I mean...it will take me weeks to dial it myself since this thing sips gas...

[talnlnky]

hmm... thats a good question... seems like mine is usually around 6-7... but it fluctuates on mine.... Also... you're hundreds of miles away from me... not sure if environmental factors change that or not.

I'm starting to think that making drastic changes in driving habbits might trick the scanguage into thinking the car got better or worse mileage than it really did.

Oh yeah... nice name...but what would I call you if I were to say your screen name in real life? "this computer"??? hehe I can just imagine it now...
Me: So This Computer was talking to me yesterday about his yaris...

[talnlnky]

yesterday my offset was around 10. Weather is colder now... and i'm having to deal with more traffic on my way to & from work now. Mpg's have tanked recently.

[127.0.0.1]

Originally Posted by talnlnky

yesterday my offset was around 10. Weather is colder now... and i'm having to deal with more traffic on my way to & from work now. Mpg's have tanked recently.

mpg's will tank...winter is coming...that means winter formula gas for those areas that do not have a lot of alcohol in the gas already

[BailOut]

My offset is 4-6% in summer and 10-11% in winter.

[talnlnky]

Originally Posted by 127.0.0.1

mpg's will tank...winter is coming...that means winter formula gas for those areas that do not have a lot of alcohol in the gas already

yeah, gas in oregon always has high alcohol content... Scanguage reports Air intake at 42 in the mornings... I'm thinking of making some sort of grill-block this weekend, see if I can get my warmup times reduced. It takes me about 3 miles to get my temps up to 170F driving normally.

[SpaceShot]

my offset has been around 7% for most of the year

[127.0.0.1]

got my percentage to a consistent 3.9%

cutoff is set to 16, because

DFCO won't occur until TPS 15,
and when I used the DFCO thread recommended set to 21,
it showed 9999 when there is no way DFCO could be engaged.

so I watched TPS and found that DFCO never occurs unless TPS is 15,
and even then, not always does DFCO engage. engine speed vs decel rate matters too.

set to 16 I only see 9999 when I know DFCO hits and never at odd times.

[SaerinRhoe]

If 127.0.0.1 ever hosts a Yaris meet, you could call him localhost. :)

As for my SGII, I think the average offset is around 5% for me. It's changed a little with the cooler weather here in North Texas but it's been approximately 5% since I bought the car in March.

S.R.

[frbl]

127.0.0.1, with your more accurate setting for DFCO and lower offset are you seeing more consistently accuraet MPG readings at fillup? In other words, are you seeing less of a need for adjustment at fillup?

I have my settings similar to everyone else's and am constantly adjusting at fillup time.

[127.0.0.1]

Originally Posted by frbl

127.0.0.1, with your more accurate setting for DFCO and lower offset are you seeing more consistently accuraet MPG readings at fillup? In other words, are you seeing less of a need for adjustment at fillup?

I have my settings similar to everyone else's and am constantly adjusting at fillup time.

well so far very little adjustment. but I still have under 1000 miles so I need
time. after 2 tanks at 16 cutoff, same pump...first tank was nailed, second one was .1 % off.

I just know that my 9999's only hit when I can be in DFCO. it used to hit on the
highway foot off the gas... but you do not always DFCO on the highway because
doing so would slow you down too much. DFCO has it's sweet spots programmed into
the computer so the thing doesn't 'buck' so to speak...

PZEV is partial zero emission vehicle, not 'always' zero emission vehicle

[talnlnky]

yeah....not sure what my DFCO cutoff is set for... I wanna say 17... but there are times I suspect DFCO isn't engaged but the SGII shows it... but that might be a refresh/delay issue more than anything else. It seems I have to adjust by .1-.3gallons each time I fill up. I probably nail it (within .04gallons 10-20% of the time.

[enkid]

Summer fuel - 3
Winter fuel - 6

[sbergman27]

I'd like to present my understanding of how the cutoff feature works and get corrections and feedback if I'm off.

The scangaugeII uses the open-loop condition to recognize DFCO. However, there are 4 conditions which can cause open-loop operation on the Yaris, and FI systems, in general:

1. Engine cold.
2. Wide open throttle.
3. Diagnostic failure (bad sensor, broken wire, etc.)
4. DFCO.

The ScangaugeII cutoff feature no doubt ignores the open-loop when the engine is below a set temperature or when a diagnostic failure is detected. However, different cars have different scales wrt the TPS. My 2008 Yaris ranges from 16 at idle to 80 at WOT. The cutoff is simply the value above which to ignore open-loop for the purposes of detecting DFCO. So... it doesn't have to be precise.

I've heard people say that the default value (24?) gave them 9999 when they didn't think the engine could be doing DFCO. But I don't understand that. How could a warm engine with no diagnostic problems be in open-loop mode at anything near the default cutoff value?

I do find that I need to set mine to the idle value + 1 to get a 9999 reading. Apparently, the TPS must be < and not just <= the cutof value for it to work. But there should be no functional difference between 17 and 24. In fact, any value up to the point where the engine goes open-loop for WOT mode should be equivalent to 17. Either the engine is in open-loop and doing DFCO or it is not, regardless of the TPS as long as it is below the open-loop point for WOT. (Which I imagine is actually less than 80.)

-Steve