Long Road Trip - Fuel Mileage - DIC vs. Actual
07-14-2008, 01:29 PM
#41
Melting Slicks
Just made a trip to Rockwall and back this weekend. I reset Trip B on the DIC and the trip function on my Nuvi so both were synchronized. When I got home my Nuvi indicated 131.0 miles and the trip meter on the DIC also read 131.0. 
Any error in the gas mileage has to be from calculating the amount of gasoline used. How is this measured? Fuel injector cycle times, a flow meter somewhere?
Any error in the gas mileage has to be from calculating the amount of gasoline used. How is this measured? Fuel injector cycle times, a flow meter somewhere?
There is a metal detector in the right pedal, especially sensitive to lead. I guess they also check the injector pulse bandwidth.
07-14-2008, 01:39 PM
#43
Instructor
Member Since: Jun 2005
Location: Houston Texas
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Trust your DIC
I would trust my DIC, it is measuring the actual gas used (flow meter) and computing against the mileage. When you fill up you may vary the amount that you put in, sometime more, sometimes less - that will make the calculations vary. Also, gas pumps can vary on accurancy, again allowing for error.
07-14-2008, 04:26 PM
#44
Safety Car
I just got back from a 4000 mile trip with the wife and a load of luggage. I occasionally checked the speedo reading against the GPS and found them to be the same.
07-14-2008, 04:47 PM
#45
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CI 2-3-4-5-6-7-8-9-10-11-12
Wounded Warrior Escort '11
St. Jude Donor '03 thru '24
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That's my experience. Previously my experience has been that the DIC fuel economy reading was move favorable than manual calculation. Wtih my Z51, MN6, stock C6 vert, however, the DIC reports a lower MPG reading than manual calculation indicates.
Last week, for instance, I drove 550 miles, mostly highway speed (75 mph) with a DIC indicated average of 25.3 mpg. Manual calculation showed 29.1 mpg. Typically, it's not that much variance, but each comparison I've done shows better mpg than the DIC indicates.
As to haters who think our cars are gas hogs, I like to ask them what kind of gas mileage they get on their four-bangers and six-bangers. Typically, I'm getting better and having more fun at the same time.
