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Discussion Starter · #1 ·
I took this pictures this afternoon:

Car Vehicle Odometer Auto part City car

1.6 L/100 KM => 147 MPG. With rounding to the nearest 10th of a liter/100 KM the actual conversion is between 142.6 and 151.8 MPG.
 

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Discussion Starter · #3 ·
I'm not sure when my car did this. I suspect it was while driving back from Laramie, WY on US 287 to Ft Collins, CO. It could also have been my day trip around Colorado last fall where I recorded 80.1 MPG on the 56 mile stretch from Fairplay to Bailey, CO.
 

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Discussion Starter · #4 ·
When I saw this this evening I was simply checking to see how my car was doing as it had been sitting at 50 MPG almost all the way home. I had been driving for 20 miles with the 25 mile readout showing 50 MPG and I wanted to see what it was really doing. Based on past experience on my commute I expected to see 3.2 to 3.5 L/100KM, certainly not what I saw. Thus the picture.
 

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Discussion Starter · #6 ·
LOL talk about return in investment. Is that a lot of DFCO action?
I'm positive DFCO played a major role in this. On level ground I run right around 48 MPG at 60 MPH.
 

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Am I missing something here? The photo shows 15.3L/100KM, which is only about 15mpg average.

100 kilometers is only 62miles, so even at EPA window sticker mpg numbers that's less than 2 gallons burned(making the average inaccurate based on the small sample size). 1.6L "best" is only for 40Km which is only 24miles, making any error even greater.

1.6L burned for 40Km is pretty exceptional MPG, but its not 147MPG. 40Km is 24.85 miles, 1.6L is 0.422 gallons, which is equal to 59.16mpg. Subtract 10% from that number for the DIC inaccuracy's, your at a real world 53.25MPG.

A prime example of why you shouldn't look at a small sample size for MPG happened to me this summer. I was driving a 2015 Tahoe 4x4 5.3L V8 in the mountains, my 50 mile average was almost 41MPG!!!! However real world average with the truck on the highway is around 22mpg. Even if I managed to get 100 miles at that rate, I doubt much of that would translate to MPG at the pump considering then were talking about 20+ gallons of fuel in the average.
 

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Discussion Starter · #8 · (Edited)
Am I missing something here? The photo shows 15.3L/100KM, which is only about 15mpg average.

100 kilometers is only 62miles, so even at EPA window sticker mpg numbers that's less than 2 gallons burned(making the average inaccurate based on the small sample size). 1.6L "best" is only for 40Km which is only 24miles, making any error even greater.

1.6L burned for 40Km is pretty exceptional MPG, but its not 147MPG. 40Km is 24.85 miles, 1.6L is 0.422 gallons, which is equal to 59.16mpg. Subtract 10% from that number for the DIC inaccuracy's, your at a real world 53.25MPG.

A prime example of why you shouldn't look at a small sample size for MPG happened to me this summer. I was driving a 2015 Tahoe 4x4 5.3L V8 in the mountains, my 50 mile average was almost 41MPG!!!! However real world average with the truck on the highway is around 22mpg. Even if I managed to get 100 miles at that rate, I doubt much of that would translate to MPG at the pump considering then were talking about 20+ gallons of fuel in the average.
I had just stopped at a stop sign after moving forward at idle in 1st gear when I took the photo which is why it shows an Instant value of 15.3 L/100 KM. The current running 40 KM (25 mile) average was 3.8 L/100 KM (61.9 MPG). The "Best" 40 KM moving average is the 1.6 L/100 KM (147 MPG). This is the 2012 ECO's game display.

The conversion between L/100 KM and MPG is 378.5411784/1.609344 / value. This formula works, unchanged, in both directions. In addition, the Cruze generally shows MPG more accurately than it does L/100 KM, which is why my original post shows the range in the post itself.

As to the argument about 25 mile averages being much higher than 50, 500 and lifetime you're absolutely correct. The pictures I took today for 50 Miles shows a 2.8 L/100 KM (82.6 MPG) Best and 4.6 L/100 KM (51.7 MPG) current running. I've had higher than this in the past but periodically reset my game displays. My best full tank MPG was a pump measured 813.9 miles / 15.6 gallons => 52.2 MPG.
 

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I'm positive DFCO played a major role in this. On level ground I run right around 48 MPG at 60 MPH.
I just looked at my sig and I'm only at like 10.1 converted.

Am I missing something here? The photo shows 15.3L/100KM, which is only about 15mpg average.

100 kilometers is only 62miles, so even at EPA window sticker mpg numbers that's less than 2 gallons burned(making the average inaccurate based on the small sample size). 1.6L "best" is only for 40Km which is only 24miles, making any error even greater.

1.6L burned for 40Km is pretty exceptional MPG, but its not 147MPG. 40Km is 24.85 miles, 1.6L is 0.422 gallons, which is equal to 59.16mpg. Subtract 10% from that number for the DIC inaccuracy's, your at a real world 53.25MPG.

A prime example of why you shouldn't look at a small sample size for MPG happened to me this summer. I was driving a 2015 Tahoe 4x4 5.3L V8 in the mountains, my 50 mile average was almost 41MPG!!!! However real world average with the truck on the highway is around 22mpg. Even if I managed to get 100 miles at that rate, I doubt much of that would translate to MPG at the pump considering then were talking about 20+ gallons of fuel in the average.
I had just stopped at a stop sign after moving forward at idle in 1st gear when I took the photo which is why it shows an Instant value of 15.3 L/100 KM. The current running 40 KM (25 mile) average was 3.8 L/100 KM (61.9 MPG). The "Best" 40 KM moving average is the 1.6 L/100 KM (147 MPG). This is the 2012 ECO's game display.

The conversion between L/100 KM and MPG is 378.5411784/1.609344 / value. This formula works, unchanged, in both directions. In addition, the Cruze generally shows MPG more accurately than it does L/100 KM, which is why my original post shows the range in the post itself.

As to the argument about 25 mile averages being much higher than 50, 500 and lifetime you're absolutely correct. The pictures I took today for 50 Miles shows a 2.8 L/100 KM (82.6 MPG) Best and 4.6 L/100 KM (51.7 MPG) current running. I've had higher than this in the past but periodically reset my game displays. My best full tank MPG was a pump measured 813.9 miles / 15.6 gallons => 52.2 MPG.
Short trips in the Cruze are really optimistic as if they just pick up where you left off. In the Accord there is no wait 25 miles to get a reading. You get in the car and move the car to the street to move another car out the driveway and BAM 8 MPG.
 

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Discussion Starter · #10 ·
I just looked at my sig and I'm only at like 10.1 converted.





Short trips in the Cruze are really optimistic as if they just pick up where you left off. In the Accord there is no wait 25 miles to get a reading. You get in the car and move the car to the street to move another car out the driveway and BAM 8 MPG.
I've noticed this as well. Both the trips I suspect that may have resulted in this were three or more hours of continuous driving.
 

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That's some impressive fuel economy!
 

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Discussion Starter · #13 ·
It shows just how good DFCO is in these cars. Consider that I tend to go up hills around 30-35 MPG, an up and back would work out to 60-70 MPG because I'm only burning gas in one direction.
 

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I have to admit I do enjoy periodically looking at the econmy screen in my diesel, however, if I had to put in metric and convert not sure I am that enthusiastic to do the math. Refresh my memory why GM did this on your 12 eco? Was it that it doesn't display miles per gallon beyond 50 or some nonsense like that?
 
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I have to admit I do enjoy periodically looking at the econmy screen in my diesel, however, if I had to put in metric and convert not sure I am that enthusiastic to do the math. Refresh my memory why GM did this on your 12 eco? Was it that it doesn't display miles per gallon beyond 50 or some nonsense like that?
I don't think the engineers at GM thought anyone would be able to drive the car past 50 MPG for any length of time. Heck, I'm not sure they even considered it. On the metric scales the car shows 0.0 to 20.0 L/100 KM. 20.0 is engine idling at a stop. 15.8 is engine idling in gear and the car is moving. By the time the 2013s rolled around they had had their misconception driven out so they allowed the car to show up to 99.9 MPG on the game displays. The 2012 ECO's trip odometers will show up to 99.9 MPG. The reason I put the car into metric is to verify that DFCO is working when I think it should be working. The ECO MT enters DFCO faster than any other gen 1 Cruze trim, including the CDT, and it stays in DFCO longer as well. Having driven an 1LT (automatic), LS MT, and a CDT (where I was specifically looking for DFCO) I think the ECO MT is in DFCO about 10% longer than the other trims.
 

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Can someone provide a brief explanation how DFCO actually works, I read that it stands for Deceleration Fuel Cut Off. How does the engine keep turning if there is no fuel there for an explosion whether it is gasoline or Diesel. I fully understand there is virtually no load on the engine and in effect you are free wheeling to some degree. Just curious what keeps the engine running. If you are driving and you run out of fuel the engine sputters for a few seconds and shuts off completely. Always like learning. Thanks
 
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Basically, the momentum of the car keeps the engine spinning. This is most effective with the MT cars. You are basically using engine braking and the computer cuts off the fuel. If you are decelerating and/or going down a hill while letting off of the gas pedal, the DFCO should engage with engine RPMs above I think 2000.
 

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Discussion Starter · #18 ·
DFCO engages whenever the car is coasting and the engine speed is above 1500 RPM. It will disengage when you press in the Clutch or the engine speed drops below 1250 RPM. It works in all gears and uses the drive wheel spin through the transmission to keep the engine turning while the fuel injectors are turned completely off. In the ECO MT it takes about two seconds of coasting to engage. In all other trims it takes about four seconds to engage. I have tested and confirmed DFCO works in my ECO MT in all six forward gears. I don't spend enough time going backwards to test it there but I wouldn't be surprised to find it works in reverse as well.

You can feel DFCO engage/disengage via the driver's seat. It feels like very small power drops (engaging) and surges (disengaging) and when descending a long shallow slope the ECU can engage/disengage about every half second. This has led to a few complaints about the car feeling like it's surging while coasting down long shallow descents. You can also see your car in DFCO by switching the DIC to Metric and watching the instant fuel economy readout. DFCO is represented as 0.0 L/100 KM. Note this display only updates about every second so you can actually get an engage/disengage cycle faster than the DIC will show.
 

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All I can say is if you think any of these figures are true,I'm thrilled for you,but I put any cars trip computer information in the same category as politicians promises,my belief is the only way to get a true reading and consumption figures is to keep detailed logs of milages and fuel puit in your tank then work it out manually.
 

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All I can say is if you think any of these figures are true,I'm thrilled for you,but I put any cars trip computer information in the same category as politicians promises,my belief is the only way to get a true reading and consumption figures is to keep detailed logs of milages and fuel puit in your tank then work it out manually.
On that note here is a direct comparison between the two methods taken on my 2013 1.6L T Petrol Manual.
numbers are L/100km fuelled up about 45-50L each time.
Trip ComputerCalculated
8.48.5
9.69.6
8.58.9
8.68.5
7.87.8
8.48.6

note:The large difference on the 3rd row is due to me misplacing the receipt before recording the data so i had to use estimated figure in my calculation.
From this I am pretty happy to use its accuracy as a guide at any given time.
 
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