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Does anyone keep their actual fuel economy numbers based on what they pump at the station and miles driven? I have noticed that while I get roughly the MPG estimates that came with the car based on the vehicle computer, the actual numbers are about 2 mpg lower than the computer. This is after about 3K miles of data so far. Does anyone else have this problem, and might there be an explanation for the difference?
 

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Same for me - but do a search - this topic has been addressed
 

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I'm tracking mine by DIC MPG, trip miles / gals, total miles. So far total average is 26.5 and the DIC is always reading too high.
 

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MACATOWA said:
I'm tracking mine by DIC MPG, trip miles / gals, total miles. So far total average is 26.5 and the DIC is always reading too high.
My theory is that the DIC disregards idling gas usage.
 

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I have noticed that while I get roughly the MPG estimates that came with the car based on the vehicle computer, the actual numbers are about 2 mpg lower than the computer.
I agree. I consistently get numbers at the pump that are right at 2 MPG less that what the DIC indicates. My average to date is 25.4 MPG (based on fuel purchased).
 

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My DIC reading MPG is about 1 less that what I calculate..Miles driven divided by gals bought at pumps
 

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Couple thoughts on this issue---DIC does in fact figure in usage while at idle. If you've recently reset the MPG DIC indicator, you can watch the MPG go down while sitting at a long redlight so I don't think that's the reason for any discrepancy. I think the "factory" calibration is actually a little optimistic for the DIC. I'm seeing about an averge 1-1.4 MPG difference between the DIC and my Scangauge II which you can actually recalibrate at each fillup. Got 3500 mi on the Terrain now and am getting consistent 27-28 MPG for each tank...about 70% HWY to 30% city. By the way, excluding redlights and stopsigns, the I4 produces amazing mileage in the 30-45MPH range. Only mileage disappointment is when my right foot gets heavy on the Interstate...it really sucks over 70MPH. But the ride and comfort makes me forget that!
 

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Islander > I found this at Amazon: "The ScanGaugeII is a 3-in-1 automotive computer that combines a multifunction trip computer, diagnostic scan tool, and up to 37 digital gauges in one small package. It connects easily to your vehicle's On-Board Diagnostic (OBDII) port and communicates directly with the vehicle's computer. Not sure if your car uses OBDII or Controller Area Network (CAN)? The unit will automatically determine which system to use and switch to it. The ScanGaugeII works on all 1996 or newer OBDII cars, including gas, diesel, propane and hybrid vehicles, as well as vehicles with the latest CAN systems. A detachable cable allows for easy transfer between multiple vehicles. Its menu-driven operation means there's no need to memorize complex sequences, and no tools are required for installation."

Where on the Nox is the OBDII port you connected it to, in engine compartment or in the interior? Where did you put the monitor?
 

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Jer---There's a thread or 2 on this. The short is that I never permanently installed the unit yet. The OBDII hookup is under driver's dash. I just plugged it in without running cable or installing the monitor permanently. Looking at the cubby in front of the shifter as a possible permanent home...one of these days. SGII is a great device. Look for the thread--lots of info.
 

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Thanks, will look for the thread.
 

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Islander said:
Couple thoughts on this issue---DIC does in fact figure in usage while at idle. If you've recently reset the MPG DIC indicator, you can watch the MPG go down while sitting at a long redlight so I don't think that's the reason for any discrepancy. I think the "factory" calibration is actually a little optimistic for the DIC. I'm seeing about an averge 1-1.4 MPG difference between the DIC and my Scangauge II which you can actually recalibrate at each fillup. Got 3500 mi on the Terrain now and am getting consistent 27-28 MPG for each tank...about 70% HWY to 30% city. By the way, excluding redlights and stopsigns, the I4 produces amazing mileage in the 30-45MPH range. Only mileage disappointment is when my right foot gets heavy on the Interstate...it really sucks over 70MPH. But the ride and comfort makes me forget that!
Okay I will retire the theory that the DIC doesnt count idle gas usage. phsst...gone..
 

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By Roesterman: Okay I will retire the theory that the DIC doesnt count idle gas usage. phsst...gone.
Ohh, too bad! I thought it was one of the most inventive theories presented at this forum. I was pulling for it to be true. ;D
 

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We have hunting land about 60 miles north of home. I usually take the 2500HD truck, utility trailer and quad and various misc tool and supplies when I go. At 12 mpg with the truck I usually use 10 gallons or roughly $30 each trip. I did the same trip with the same gear and I spent $23+ on gas in the I-4 Nox. Cant really say Im impressed with the mileage but I am impressed with the car.
 

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Just an FYI.
Did a test the past two weeks to see how poor the MPG could get by driving hard.
Used M and constantley ran to 4-5 thousand RPM and sometimes to 6. Down shifted a lot and idled a lot. Just filled up and the result was 17 mpg.
 

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Guys, unless you have around 10k miles on the motor, its not going to give you the best MPG. Heck, there are some reports the DI engines from GM dont fully get the best MPG until around 20k miles on some Cadillac forums with the HF 3.6 V6. Same with the Camaro.

Having said that, our DIC has always been about 1 MPG too high. On a recent highway trip it was almost dead on. Not sure why but it was.
 

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My DIC averages around 25, and actual mileage averages 23.5

Better than my Avalanche, but honestly I hoped it would be higher.

Kevin
 

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ccharlie said:
Just an FYI.
Did a test the past two weeks to see how poor the MPG could get by driving hard.
Used M and constantley ran to 4-5 thousand RPM and sometimes to 6. Down shifted a lot and idled a lot. Just filled up and the result was 17 mpg.
Driving like that means nothing (you could just set it in N and floor the pedal ;D).

I think load it to the roof, floor it and break hard very often would mean something. But is still useless... The point is getting better economy, not worst.
 

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Personally I feel the Equinox/Terrain get decent fuel mileage in 4 cyl and 6 cyl for the type of vehicle that it is. That being a relatively large "compact" CUV with a fair bit of weight and a very decent comfortable ride.

If I wanted extreme fuel economy numbers I might of bought an Aveo or Yaris, etc. If I didn't give a **** about mileage maybe I would of bought a V8 Land Rover or gas guzzling Jeep Commander. ::)

Basically the Nox/Terrain yield respectable fuel economy in a comfortable and sexy package which can definitely be altered one way or another by driving style, road conditions, weather conditions and landscape. Becoming too focused on the fuel economy detracts from the vehicles other attributes.
 

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bballr4567 said:
Guys, unless you have around 10k miles on the motor, its not going to give you the best MPG. Heck, there are some reports the DI engines from GM dont fully get the best MPG until around 20k miles on some Cadillac forums with the HF 3.6 V6. Same with the Camaro.

Having said that, our DIC has always been about 1 MPG too high. On a recent highway trip it was almost dead on. Not sure why but it was.
That's good to hear that the engine needs 10,000 to 20,000 miles before it loosens up and maximizes the gas mileage. As I posted earlier in another post, on a recent trip, I was very careful (soft on the gas pedal) for the entire trip and only averaged 25 MPG. This was actual mileage, calculated by dividing miles driven by fuel used. I was dissappointed because I don't intend to drive the interstates at 50 to 55 MPH for the life of the vehicle. I'll just be patient and put some miles on it before getting concerned.
 

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Fanman, search for my thread that I started on fuel economy. I think youll be surprised at how GOOD FE the vehicles can get if you slow down some.
 
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