Might check out a discussion that we had going over on CleanMPG in the thread 'ScanGuage Comparison'. We had a lot of back and forth trying to desicde just how the NAV Avg MPG was computed. Don't know if we ever came up with any true answer - just more questions.

 

I thought the mpg display was for the past 15 minutes. That's what the text on the screen says at least.

That would also explain how easily you effect the MPG.

 

The average displayed is not over the last 15 minutes but is carried over until reset. The 15 minutes refers ONLY to the graph in the background. Otherwise it should instantly read 0 when you turn on the car!

 

I also called that average the 15min average because of the way nothing is spelled out as to what it is. Tim's right in saying the 15min average is just the graph. The graph, and the bar instant mpg are useless on the Navi IMO.

If you are a high MPG driver, the data will not be stored for an entire tank on the Navi. On my Navi, about half the data is dropped at about 350 miles and new data may change your tank average. All and all, it's still better than measuring at the pump for you tank average. I've compared and continue to compare the Navi to the SG for tank averages, and the SG seems to be more accurate because it has not dropped any data on a single tank that I know of.

My plan is to get the SG11 in August and hook it to my pocket PC via USB to my docking station. I'd like a PC program for a better battery SoC meter. Got a kid at MIT that will hopefully help us all out here. He owes dad a few favors, and it may be an idea for a new start up company to put that computer program together.

GaryG

 

Kermie,

To reset the average in the message center, go to the AVG Econ display, and hold the set button until it beeps/resets.

 

Tim is correct - You are actually looking at 3 different sets of data. The 'Instant MPG' bar graph, the last 15 Min Average graph and a horizontal line with the Avg MPG since you last pushed the 'Reset' button.
That Avg MPG could be over 1 mile or 10K. Most hit the 'Reset' button at each fill-up but I guess you could never hit the re-set and the average would be from whenever the reset was last pushed - be it 1 mile ago or ~.
Like Tim said - if it were just for the last 15 mins then you would be starting all over at Zero - even if you just went into the shopping mall for 20 mins.
The discussion we were having over on CleanMPG was - how does the unit carry over the old data - average out the last 2,000 data points and start a new set with that being the base. I think we did come to the conclusion that it was not based on 1 data point per min (as reflected on the 15 min average graph - which is of no use at all unless you are out on the expressway for long distance etc) because as you or someone pointed out the Avg MPG goes up and down by seconds and not minutes. I am also curious about the reading jumping so much even if you had not reset the computer and were working on 2,000 miles but the avg would change just as fast as if you were working on the last 100 mile of a single tank. You would think that it would take a lot longer for a change since you are working with more Miles and Gals so the overall affect should be small.

 

Phillip, that is a great round trip on your sig page. The Navi can be reset to determine an accurate RT, to find short MPG segments while drafting and tank averages. My EB Explorer has that same capability with the running MPG average in the message center like the non Navi FEH. You can get the same info just by resetting it in that mode. Some people reading this thread may have not known about this untill now. Everyone should reset their average at fill-up to get the real MPG on their tanks, RT's and any segments they want.

It's time for AWD and FWD FEH owners to accept that FEH can stay in the 40mpg range after there broke in. Your AWD has to be much more capable of 42mpg to average that in that long of a RT.

GaryG

 

Gary, here's a free program that runs on the Palm....not sure if it would give all of the readouts from a hybrid but maybe worth a look. You'd need a $85 OBDII cable.

 

Hi Tim

I guess the link didn't make it to the thread. My Son has the Palm pocket PC, and I've got the UTStarcom VX6700, both with Verizon broadband. I use Windows Mobile, but he told me there is a faster system he uses that I'll try when he comes down this month. This unit is my mobile phone, digital camera and digital video all in one. Not sure if these systems will work thru the OBD11 directly. A laptop for me is not in my future at the moment.

The new SG11 with the USB connection may give me the access through it's OBD11 cable. If there is a way to do it, Matt can. He wrote programs for Palm two summer's ago, and now is finishing up with McAfee who bought Siteadvisor, a program he helped design. BTW, I offered a copy of Siteadvisor free here. That small company sold for 80 million. Stock options are nice!


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Real Name: Gary Gattis
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Hybrids: 05 FWD Escape Hybrid
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[img]images/icons/icon1.gif[/img] Re: Miles To Empty



OT - Merry Christmas everyone here at Greenhybrid.com. My son took off a year from MIT to help a company develope a security software program. Its rather unique as it test websites and warns you before you click on them. Its designed to work with Internet Explorer or Mozilla Fire Fox. My son wrote the entire Mozilla and part of the Internet Explorer program. It will work in addition to your existing security programs.

Your welcome to download it for free as they are allowing people to try it before its released early 2006. Of course I have the program downloaded on my three computers and my wife's office computers and it works great. Newer versions will be updated in the future at a cost but you can always keep this version and pay nothing. This is our Christmas gift from us and Siteadvisor. Read about it

athttp://www.siteadvisor.com/tellafriend.html

and download it if you want

GaryG

Don't think you can get that program unless you buy McAfee now. It's quite a nice program. Hope Matt has time for us with these gauages.

GaryG

 

I want to thank everyone for the replys to my initial message. After watching the display, and purposfully driving in non fuel saving modes I have come to this conclusion:

The white AVG mpg bar on the NAV display is only for the last 15minute avg. When you shut your vehicle down it will retain your previous 15min history avg on that white bar, then when you drive it replaces the data with your current driving avg.

Of course this is my opinion but it accounts for why the number can change so drasticly. I know it was mentioned 2000 data points but that would keep the number from changing as quickly as it does or ........ maybe it's 2000 seconds of data = 33.333 minutes (2000/60) this would also alow for quick changes.

Also if it pages the data that would be two 15 minute pages:
1st pg is the data shown when you start your vehicle as you drive it then gets overwritten with the 2nd page of data.

In my opinion - this is virtually useless data as I would rather have a full tank or multiple tanks worth of average shown on the screen.

About the only thing the data is useful for is estimating your current miles to empty display since it shows how your current 15min average.

Any thoughts?