Fuel Used

[T-pole]

Does anyone check the fuel (gallons) used against the gallons pumped when filling up?

I only have about 3,000 miles on my truck. My last fill up, my gauge said I used 22.8, and I pumped 24.06.

The time before, my cluster said I used 22.5 gal, and I pumped 24.3.

Just wondering if the truck is off, or if the pumps are cheating me.

 

[1stimeyukon]

mine is usually off but not by 2 or more gallons like yours. i usually pump about half a gallon more then i use and i hav e about 8 thousand miles on mine and it has been like that ever since i bought at every gas station all throughout southern california

 

[bad63lac]

I never reset mine. I like the sickening thought of knowing how many gallons I've used over the life of the vehicle.

 

[1stimeyukon]

thats not a bad thought. i think imma start doing that instead.

 

[chadwick02]

i check mine fairly often and reset at each fill up. I want to know if DIC is accurate or not, and for me so far it has been. My fuel used has been accurate typically within .5 gallons and DIC average MPG vs my calculated MPG is typically within .75 of a mile per gallon.

 

[Landshark]

My 07 Kon is pretty darn close to what the "gallons used" says. I too reset mine every time...not sure why.

 

[TN Tahoe]

Does anyone check the fuel (gallons) used against the gallons pumped when filling up?

I only have about 3,000 miles on my truck. My last fill up, my gauge said I used 22.8, and I pumped 24.06.

The time before, my cluster said I used 22.5 gal, and I pumped 24.3.

Just wondering if the truck is off, or if the pumps are cheating me.

Keep in mind gas station pumps will shut off at different fuel level reads. If you don't fill up the tank until fuel is at the top of the neck EVERYTIME you’re not going to get a good reading as to how much was really burned out of the tank vs. what you put in the last fill up. I have added an additional 2 gallons easy after the pump shuts off. We won’t even get into if the truck is leaning toward the pump or away from the pump (park on an incline at the station). All of this could vary how much fuel you put in the tank between fill ups. Your Tahoe monitors the fuel that is burned thought the system. In other words both could be accurate the pump and the Tahoe fuel burned information. Your fill up could vary two gallons depending on how much you get into the tank at the station vs. the last fill up. Hope this make sense.

PS: I make sure I get the tank full each time, in doing so mine is within 1/2 of a gallon of what the display in the Tahoe reads.

 

[DownTownDru]

If you use remote start, that idle time does not count on the gallons used. In the winter I am easily 4-5 gallons off from the DIC. Summer time the DIC and pump meter is a lot closer since I don't remote start it.

 

[chadwick02]

If you use remote start, that idle time does not count on the gallons used. In the winter I am easily 4-5 gallons off from the DIC. Summer time the DIC and pump meter is a lot closer since I don't remote start it.

Wow, that's interesting, I never thought about that. Are you sure it doesn't count fuel used while being remote started?

And 4 or 5 gallons out of every tank? That seems like a lot of fuel to warm up your truck to me!

 

[TN Tahoe]

Wow, that's interesting, I never thought about that. Are you sure it doesn't count fuel used while being remote started?

And 4 or 5 gallons out of every tank? That seems like a lot of fuel to warm up your truck to me!

I agree.. I don't think that is correct at all.. I use my remote start all the time and I have not seen the pump reading differ from the fuel used by more then a 1/2 gallon

 

[DownTownDru]

I agree.. I don't think that is correct at all.. I use my remote start all the time and I have not seen the pump reading differ from the fuel used by more then a 1/2 gallon

I'm positive on this having owned the truck through 2.5 winters. I have an early build 07 (March 2006) so maybe this does not affect all of the new generation models.

Our winter temps are often single digits in the morning (we had -19 to -22 air temps last week) with high winds (and a wind farm to prove it) so 15-20 minutes of idle time every morning not uncommon. My commute is less than 5 miles so the idle time fuel consumption doesn't average out very well over the tank.

In the summer when I don't use the remote start my DIC is within 1/2 gal of the pump meter almost every time.

 

[bad63lac]

False.

Idle time consumption is 100%, absolutely, without a doubt figured into the economy statistics for both Gallons Used and Average MPG.


It does not only keep track of these stats while in motion. Idle is measured too. The amount of fuel delivered through the injectors is calculated at all times.


Reset your average MPG. Drive a very short distance (coast a few hundred feet). Observe the AVG MPG. Sit there and idle and it will go down in front of your eyes.

 

[DownTownDru]

False.

Idle time consumption is 100%, absolutely, without a doubt figured into the economy statistics for both Gallons Used and Average MPG.


It does not only keep track of these stats while in motion. Idle is measured too. The amount of fuel delivered through the injectors is calculated at all times.


Reset your average MPG. Drive a very short distance (coast a few hundred feet). Observe the AVG MPG. Sit there and idle and it will go down in front of your eyes.

I'm not talking about key-in idle, I'm talking about remote start idle. Do you have factory remote start? Have you verified this?

 

[TN Tahoe]

I'm positive on this having owned the truck through 2.5 winters. I have an early build 07 (March 2006) so maybe this does not affect all of the new generation models.

Our winter temps are often single digits in the morning (we had -19 to -22 air temps last week) with high winds (and a wind farm to prove it) so 15-20 minutes of idle time every morning not uncommon. My commute is less than 5 miles so the idle time fuel consumption doesn't average out very well over the tank.

In the summer when I don't use the remote start my DIC is within 1/2 gal of the pump meter almost every time.

Will do some checking you got me wondering now. I live in a mild climate so I use the auto start in the winter but not all the time.

 

[73shark]

Don't know about the remote start but do know that if you fill the filler neck, you will have a problem, most likely in the evap. control system. I fill my at the same pump and stop when the pump does and the DIC is always a bit optimistic.

 

[07SuburbanLTZ]

I check mine all the time and if the DIC says that I used 26.1 gallons I'll pump 26.1 gallons. Sometimes it may be off by .03 ether way, but not much.

 

[T-pole]

Keep in mind gas station pumps will shut off at different fuel level reads. If you don't fill up the tank until fuel is at the top of the neck EVERYTIME you’re not going to get a good reading as to how much was really burned out of the tank vs. what you put in the last fill up.

Yeah, that does make sense. I didn't post my first tank (which was almost 3 gal short of what I pumped). So, 3 fill ups in a row, they were all short, thats what got me thinking. If they varied (some high, some low) I'd be with you on this.

If you use remote start, that idle time does not count on the gallons used. In the winter I am easily 4-5 gallons off from the DIC. Summer time the DIC and pump meter is a lot closer since I don't remote start it.

That could be. I'll test the remote start tomorrow morning to see. I reset the MPG's on my drive home tonight. Drove about 30 miles, and I'm right at 24 MPG. So, if I let it warm up for 5 min tomorrow, it should be well below 24 MPG if it factors that in.

Thanks for all the replies.

 

[bad63lac]

That could be. I'll test the remote start tomorrow morning to see. I reset the MPG's on my drive home tonight. Drove about 30 miles, and I'm right at 24 MPG. So, if I let it warm up for 5 min tomorrow, it should be well below 24 MPG if it factors that in.

Thanks for all the replies.

30 miles is too much. You have to factor in that while driving a lot more fuel is being pushed through the injectors than when idle. A few minutes of idle wont affect it that much.


In any case, for sh!ts and giggles, I did the test and like I said, it does factor it in...


-Took a trip to the store last night
-On the way home reset my AVG MPG when I was 4 blocks from home
-Pulled in the driveway and my AVG MPG reading was 16.4
-Turned off the truck
-Remoted started twice (20 minutes idle)
-My AVG MPG was now 16.0



Again, the computer keeps track of how much fuel it delivers through the injectors. It does these calculations whenever the engine is running in order to provide the proper fuel mix. It does this whether you are driving, idle or remote started w/o the key in the ignition. It does not matter.

 

[DownTownDru]

FWIW, my GF has an 09 Malibu and she has the same driving conditions and warm up conditions as me and is also using a factory remote start.

Her MPG computer does appear to factor in remote-start idle time since her MPGs on the 4 cylinder Malibu drop from 22+ city to around 14-15 city now that we are in winter.

As I said before, my early build 07 Tahoe may very well have a software glitch that is resulting in my remote start idle time not counting in the DIC metrics. bad63lac, thanks for checking.

 

[T-pole]

-Took a trip to the store last night
-On the way home reset my AVG MPG when I was 4 blocks from home
-Pulled in the driveway and my AVG MPG reading was 16.4
-Turned off the truck
-Remoted started twice (20 minutes idle)
-My AVG MPG was now 16.0

Try this. Reset your AVG the same distance away (or farther). When you get home, put the truck in park, while idling, and watch how fast the MPG's drop over a matter of minutes.

I agree that idle uses less fuel then driving, but 20 minutes of the truck running will drop the average much lower then .4 with such a short distance on the clock.

This morning I remote started the truck for about 5 minutes, and no change in MPG's. Drove to work (about 10 miles) and the truck was at about 22.5 MPG.

Leaving work, I got stuck at a red light for about 2 minutes. During that time, my AVG dropped from 22.5 to 22.0, and that was with about 40 miles built into it.

Again, I'm not arguing with anyone, just trying to figure out why my DIC gallons used was so far off of what I pumped. Mostly trying to make sure that the gas stations weren't screwing me.:confused2: