I just drove on a 220 mile trip to the north woods of Wisconsin and looked at me edge cts and it said I was averaging 13.1 mpg so I checked what my truck said and it showed 21 mpg and there is no way I used 17 gallons of fuel cuz i still have a 3/4 tank (and that would be crazy seeing as it was me wife and the kido so not a load at all ). I was wondering how accurate these things are. Only mod on the truck is a s &b intake (just changed air filter before the trip).
Ya I am going to when I get a chance to get to the gas station. I hand calculated on wed and I was at 16.8 straight city driving. I know they are going to different but not expecting it to be that different. Also I was just wondering cuz i am going to be doing a full delete and new up pipe and down pipe and exhaust with Pyro probe. And a Kory tune but wanted to watch the rail pressure and egts
For all the direct sensor readings, the CTS is pretty accurate. Fuel mileage is kind of a wild card because it calculates it based on what the ECM tells it the injectors are injecting at each firing event. Nothing is very accurate when it comes to figuring mileage, there are too many variables in the system. Even GM didn't get it right with the DIC calculator.
I have stock tires on, do I still have to input the size?
Ironman thats good to hear that they are accurate I knew they wouldn't be the same but didn't think they would be that off. Do you have the edge cts? (Can't see the signatures on my phone)
I never could make any sense of either the avg or instant mileage on my CTS compared to the DIC. The CTS numbers seem all over the place and I don't see any way to reset the avg mileage like you can with the DIC.
Its pretty easy to characterize the DIC based on a few fillups. Mine is consistently 5-6% over on avg MPG as it always under calculates "fuel used" by that amount on each fillup.
Yes I have the CTS. I believe you have to enter the size in twice to verify. You enter the oem size, then what ever size you are running.
Check that, but also remember the CTS is giving instant MPG.
After messing around (for while) with the cts I have (should be the same right) go to the mileage coach and there is an option to rest the average econ. It will ask you to confirm and hit yes.
I do have a CTS and for things like the coolant temp, it's more accurate than the dash gauges. The fuel mileage calc is always going to be off though, it's a best guess estimate and there are enough losses in the calc that it's never going to be all that accurate.
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