DIC Range
02-15-2013, 04:27 PM
#1
Racer
Thread Starter
DIC Range
On my 2011 coupe with 6 mn after filling up and driving a few miles the range would show 430 miles or so. But on my 2013 Grand Sport with same type driving after filling up the most it will show is 330 miles. Could a sensor or software be off???
02-15-2013, 05:03 PM
#2
Melting Slicks
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St. Jude Donor '11-'12-'13
I believe its based on the average mpg displayed in the fuel part of the dic.
I filled my tank and started on a long hwy drive without resetting the mpg and as I drove ( getting much better "instant" mpg on the hwy) about 100 miles my range only dropped about 25 miles or so.
If that makes sense
the higher your average mpg the farther the range per tank.
I filled my tank and started on a long hwy drive without resetting the mpg and as I drove ( getting much better "instant" mpg on the hwy) about 100 miles my range only dropped about 25 miles or so.
If that makes sense
the higher your average mpg the farther the range per tank.
02-15-2013, 06:01 PM
#3
Racer
Thread Starter
I believe its based on the average mpg displayed in the fuel part of the dic.
I filled my tank and started on a long hwy drive without resetting the mpg and as I drove ( getting much better "instant" mpg on the hwy) about 100 miles my range only dropped about 25 miles or so.
If that makes sense the higher your average mpg the farther the range per tank.
I filled my tank and started on a long hwy drive without resetting the mpg and as I drove ( getting much better "instant" mpg on the hwy) about 100 miles my range only dropped about 25 miles or so.
If that makes sense
the higher your average mpg the farther the range per tank.
02-15-2013, 06:03 PM
#4
Wil Cooksey #256
After a day at the track I fill up and my range is something like 180 miles. After traveling 100 miles on the freeway my range is about 190.
So, yes it does have something to do with average MPG. If anyone has driven from CA to AZ and filled up in Albuquerque one would think the range function is broken. Two summers ago I filled in Albuquerque and my range was 499. There is a very long downhill going into Albuquerque and you are coasting most of the way, inst MPG is about 77.
So, yes it does have something to do with average MPG. If anyone has driven from CA to AZ and filled up in Albuquerque one would think the range function is broken. Two summers ago I filled in Albuquerque and my range was 499. There is a very long downhill going into Albuquerque and you are coasting most of the way, inst MPG is about 77.
02-15-2013, 07:02 PM
#6
Team Owner
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St. Jude Donor '13
It sure would be nice to know exactly how the system predicts your range. It seems to be based on the last xx minutes/miles, but not a simple mean average.
IIRC, I can sit in traffic for a couple of minutes and the range doesn't drop, but after a while it starts dropping significantly as the car realizes it's getting 0 mpg right now.
It also seemed that resetting the Average MPG readout on the DIC, did not change the Range.
Hoping that talon90 or someone else with inside info, will chime in.
IIRC, I can sit in traffic for a couple of minutes and the range doesn't drop, but after a while it starts dropping significantly as the car realizes it's getting 0 mpg right now.
It also seemed that resetting the Average MPG readout on the DIC, did not change the Range.
Hoping that talon90 or someone else with inside info, will chime in.
02-16-2013, 12:00 AM
#9
Race Director
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The instant mileage is updated every 2 seconds. The range is based on the fuel remaining divided by the average fuel used for the last 50 miles. The low fuel warning comes on when the calculated range drops below 40.
02-16-2013, 12:48 AM
#11
Racer
The fuel sending unit has a orifice the size of a human hair somewhere around
.000672 gasoline fuel flows faster than water, as it registers slowly so your electronic fuel sending unit isn't overworking and floating its actual sampling rate is 163 SPS (seconds per sample)
.000672 gasoline fuel flows faster than water, as it registers slowly so your electronic fuel sending unit isn't overworking and floating its actual sampling rate is 163 SPS (seconds per sample)
02-16-2013, 07:09 AM
#12
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C7 of the Year - Unmodified Finalist 2021
the range takes into account your fuel consumption for the last certain miles (someone here said 50) and knows how much fuel you have left
this is my best (somewhere in Utah in hot weather):
this is my best (somewhere in Utah in hot weather):
02-16-2013, 08:23 AM
#13
Just curious, how many miles are you typically getting from fill up to gas light? If you are a mix of city and highway I'd think around 300-325. If you are actually getting 400+ then yeah you might have an issue. I know you said your averages seem to be the same, but I know it's pretty common for GS's to get worse fuel economy. Its attributed to all that extra horsepower 
Seriously though, if you figure your true average is 20mpg your entire tank from brimming full to bone dry would be 360mi if you are getting the estimated best estimated highway number at 26mpg that puts you at 468mi. Now, in my 2011 coupe I can get 32mpg on a road trip so those 525 to 550 estimated numbers become easier to see. Even then the dic doesn't figure your range based perfectly on 18.0 gallons. I just suspect your average is somewhere around 20 and the extra 30 miles you should see is either in not having exactly 18 gallons of fuel or the CPU might have a little but of a cushion built in.
Seriously though, if you figure your true average is 20mpg your entire tank from brimming full to bone dry would be 360mi if you are getting the estimated best estimated highway number at 26mpg that puts you at 468mi. Now, in my 2011 coupe I can get 32mpg on a road trip so those 525 to 550 estimated numbers become easier to see. Even then the dic doesn't figure your range based perfectly on 18.0 gallons. I just suspect your average is somewhere around 20 and the extra 30 miles you should see is either in not having exactly 18 gallons of fuel or the CPU might have a little but of a cushion built in.
02-16-2013, 10:35 AM
#15
Le Mans Master
Nope. It's a lot faster than that.
Nope. To do that would require remembering the amount of fuel used every mile or less. When you had traveled a mile you would add the fuel used in the last mile and subtract the fuel used 50 miles ago. That is far too complicated for such a simple measurement. The mileage used to calculate range is an exponential function where a percentage of the average since the last reset is added to a corresponding percentage from the current usage. If you haven't traveled a minimum distance since the last reset then the percentages would be adjusted accordingly.
Close but still not quite correct. The LOW RANGE comes on at 40 miles. According to the manual low fuel comes on when low range comes on OR at 1.8 gallons but there is a little more than that as a second safety factor.
Close but still not quite correct. The LOW RANGE comes on at 40 miles. According to the manual low fuel comes on when low range comes on OR at 1.8 gallons but there is a little more than that as a second safety factor.