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Fuel economy display

LouG

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Can anyone tell me why the economy figure differs between the trip computer mode and the actual fuel economy display? And both are really slow to update.
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pc104

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I have also noticed the fuel economy in the trip computer display becomes wildly inaccurate after a couple thousand miles. For example, the fuel economy screen will be showing 19.5 mpg and the trip computer will show 6 mpg at the same time. My best theory is a floating point error or some memory overflow when you don't reset the trip computer for a while.
 

Zig

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Can anyone tell me why the economy figure differs between the trip computer mode and the actual fuel economy display? And both are really slow to update.
Are you referring to the ‘instant’ vs ‘average’.

for example, rolling downhill with zero load instant is high but pull/pushing uphill the instant is low while traveling in the same gear.
 

Frogdog1

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Can anyone tell me why the economy figure differs between the trip computer mode and the actual fuel economy display? And both are really slow to update.
No, I can't answer your specific question. My average trip odometer fuel economy number updates pretty often.

I can't answer your question because I didn't even know there was an "actual fuel economy display" different from the trip odometer fuel economy number. How is it accessed to display? Thanks, FD
 
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LouG

LouG

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Are you referring to the ‘instant’ vs ‘average’.

for example, rolling downhill with zero load instant is high but pull/pushing uphill the instant is low while traveling in the same gear.
Neither seem to be instant in any way.
 


Zig

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Zig

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This is the instant/real time estimate display: the progress bar shows real time and the average is calculated from the duration (i wanna say lifetime but would need to reset a trip to confirm and not really wanting to do that just yet).

S650 Mustang Fuel economy display IMG_2687
 
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LouG

LouG

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Screen shot?
I'd rather not while driving.
What I mean is that cars we've had with instant consumption display it shows as a constantly changing figure in line with throttle position etc.
Neither display in the Mustang does that. It's just a figure that slowly changes over time ie, the average.
OK, I just saw your last post. Yes, I do have the sliding scale display which I don't find that useful. It's the two average read outs that differ.
 

Zig

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I'd rather not while driving.
What I mean is that cars we've had with instant consumption display it shows as a constantly changing figure in line with throttle position etc.
Neither display in the Mustang does that. It's just a figure that slowly changes over time ie, the average.
OK, I just saw your last post. Yes, I do have the sliding scale display which I don't find that useful. It's the two average read outs that differ.
Agreed regarding the sliding scale but at least it doesn’t shoot to 99 when you lift like the other guys. It’s a fun little game to play when passenger has decided to nap during the road trip.
 

Zig

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This version (from the other guys) was a tad more helpful but suffered from the 99 on lift problem. (V6 awd with cylinder deactivation and stop start). So far enjoying the v8 (non s/s version) gt more even though the display isn’t as tech heavy.

S650 Mustang Fuel economy display IMG_2692
 

Frogdog1

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My Honda shows actual real time and average on the same screen and I find both to be useful to a point.

I haven’t seen but only an average on my Mustang. It’s useful in a way but I really don’t care what the avg. is running. I’ll drive how I want.
 

davidsteele1975

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I believe you have to reset them independently; I haven't tried yet as I haven't had the car long but if you reset them close to the same time you should see the same results.
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