Average Fuel Economy Display (A vs. B setting)

[inuvik]

PityOnU - I doubt B is a lifetime average. After a certain amount of data, it will overwrite. What most would use B for is for average mpg FOR EACH TANK OF GAS. And then reset B after refueling the car. Each tank mpg is what I find interesting.

At the very least, when I'm gassing up, or anytime I feel like fiddling with it, I can switch it to B to see where it's at. The better way to set that up would have just have another viewable window. It could go into A average mpg, and the next switch of the button would be B average mpg. No need to go to the range and hold the button down to switch to B (silly).

Even though by default it will not stay on B, B does not reset until it is reset manually.

"B" average will not reset ever unless you manually zero it out (disconnecting the battery may also zero it out, never tried it). If you bought your Mirage brand new and drove it for 5 years and never reset "B" you could look at your lifetime average. "A" resets after approximately 4 hrs of not driving.

[Fummins]

That's what I always figured.^ Otherwise would it reset itself after every tank of gas? Would the sending unit hit a reset switch when it reaches full or empty? I guess that's do able.
Disclaimer: Not trying to hurt feelings or be a dick. genuinely asking an automotive engineer/designer a real question. How about your dodge? Does it have the roof mounted display? If it does it likely has both an instant and what I believe is a lifetime average economy gauge like my first, clearly under appreciated and under valued last year of production 2nd gen Dodge diesel.

[7milesout]

Yes - My old Dodge does have the OHC (overhead console) mounted display. It does display instant and average mpg. But to clarify, it is not "lifetime" average. These little "computers" will not store a lifetime's worth of data. They will overwrite old data with new. I may have actually read that in my Dodge's manual in the past, I'm pretty sure I did. But there's proof also.

In the case of my Dodge, I could tow say, 1,000 miles worth and average say ... 13 mpg. Then I could drive I don't know, maybe 5,000 miles worth. At the end the average mpg will say something like 21.2 mpg (average). There's no way the 6,000 mile average would be that high, if that 1st 1,000 miles towing hadn't been overwritten.

In the case of our Mirages. It may "seem" like a lifetime average. But that's because our average mpg doesn't drop that much, therefore doesn't vary that much. There's just no way these little doodad computers are going to store a lifetime worth of data. If Mitsubishi could save $0.25 to limit it's collectible data to some amount, say 5,000 miles, or 10,000 miles, they would FOR SURE save that $0.25. I say that with direct experience. I did lots of VAVE at Toyota. Toyota would save $0.25 as well. For example, $0.25 times 400,000 Camrys per year is $100,000. OEMs like $100,000.


7milesout

[7milesout]

Would the sending unit hit a reset switch when it reaches full or empty? I guess that's do able.

My Lexus LS 460L has this feature. As well as having an instant (bar which is dumb), and average (manually resettable) and an average (since last fillup), and other stuff (range, etc). So the one since fillup resets itself automagically at the gas station. Whenever I put it in gear and roll a couple feet it resets. How it resets, I'm not sure. I'm guessing it is related to the sending unit signal like you suggest.

[Top_Fuel]

I still have to search this forum to figure out how to view my "B" average.

And I don't remember how to reset/turn-off the wrench display.

[Fummins]

Yes - My old Dodge does have the OHC (overhead console) mounted display. It does display instant and average mpg. But to clarify, it is not "lifetime" average. These little "computers" will not store a lifetime's worth of data. They will overwrite old data with new. I may have actually read that in my Dodge's manual in the past, I'm pretty sure I did. But there's proof also.

In the case of my Dodge, I could tow say, 1,000 miles worth and average say ... 13 mpg. Then I could drive I don't know, maybe 5,000 miles worth. At the end the average mpg will say something like 21.2 mpg (average). There's no way the 6,000 mile average would be that high, if that 1st 1,000 miles towing hadn't been overwritten.

In the case of our Mirages. It may "seem" like a lifetime average. But that's because our average mpg doesn't drop that much, therefore doesn't vary that much. There's just no way these little doodad computers are going to store a lifetime worth of data. If Mitsubishi could save $0.25 to limit it's collectible data to some amount, say 5,000 miles, or 10,000 miles, they would FOR SURE save that $0.25. I say that with direct experience. I did lots of VAVE at Toyota. Toyota would save $0.25 as well. For example, $0.25 times 400,000 Camrys per year is $100,000. OEMs like $100,000.


7milesout

Good points, that makes sense. These are strange cars though. I was able to look and see how many times a Mirage was started. I posted it somewhere around here, I guess it managed to keep a lifetime record of that unnecessary info. They also did some weird things like installing the front fog light wiring on many cars, as you're aware.

My Lexus LS 460L has this feature. As well as having an instant (bar which is dumb), and average (manually resettable) and an average (since last fillup), and other stuff (range, etc). So the one since fillup resets itself automagically at the gas station. Whenever I put it in gear and roll a couple feet it resets. How it resets, I'm not sure. I'm guessing it is related to the sending unit signal like you suggest.

Weird, I'll have to look and see if mine ever resets. I'll just now assume it's a long distance rolling average on the mirage.

I still have to search this forum to figure out how to view my "B" average.

And I don't remember how to reset/turn-off the wrench display.

I can't recall how to turn the stupid wrench off, I turned mine and all the work cars off permanently. For the b-eco meter you flip to the distance til empty display then push and hold the button.