: Cts mpg vs cts-v



DPL
01-08-12, 03:37 PM
My V2 is in for some service and the loaner I have is a 2010 CTS base model. I've had it for 3 days now and the average MPG is at 17.4! My V2 gets 16ish.

I thought that was interesting.

shchow
01-08-12, 03:56 PM
I drive a mixture of highway and local traffic and I average 12mpg, and that is driving rather sedately.
Any spirited driving and I'm averaging 10mpg or less.
So 16mpg is pretty darn good...

DPL
01-08-12, 06:04 PM
You should take it in, check the tune or something. I drive the same, mix of hwy and local. I don't beat up my car but I drive it like it wants to be driven.

M5eater
01-08-12, 06:11 PM
The SRX's I've driven on loaner hit 20MPG or more combined.

HeavyH20
01-08-12, 07:29 PM
I get 16, mixed 50/50, with "fun" happening a little more than it should.

stabie
01-08-12, 08:01 PM
My 08 CTS 3.6DI got 20 in mixed in town driving and typically 26 when I took trips. I only wish my V2 was anywhere close. BUT, the DI V6 did not have near the pull power.

Gary Wells
01-08-12, 09:17 PM
ampg is actual mpg as calculated by filling tank
cmpg is computer mpg, almost always more than the actual mpg.
Most of this is around town driving, but not totally stop and go
A little freeway mileage mixed in , those would be the better mpg's.
A little spirited driving on all of it.
Never had it on a long trip to check mileage.

---date------miles---miles-----gals-----price----cost----ampg--cmpg.--spd---range

06-02-11---3516---172.0---11.430---4.199---48.00---15.0----N/A---00.0---000
06-14-11---3694---178.0---11.222---4.099---46.00---15.9----N/A---00.0---000
06-18-11---3823---129.0---13.220---4.099---40.00---13.2----N/A---00.0---000
06-22-11---3965---142.0---08.294---4.099---34.00---17.1----15.2---00.0---000
07-06-11---4092---126.4---08.335---3.959---33.00---15.1----15.3---00.0---000
07-12-11---4252---160.3---11.141---4.039---45.00---14.4----15.1---00.0---264
07-18-11---4392---139.4---08.913---4.039---36.00---15.6----15.4---31.6---266
07-21-11---4509---117.8---08.170---4.039---33.00---14.4----15.5---32.3---263
07-25-11---4656---146.0---09.752---3.999---39.00---15.0----15.4---33.0---278
07-30-11---4849---193.1---12.753---3.999---51.00---15.1----15.2---31.1---283
08-03-11---4989---140.7---08.501---3.999---34.00---16.6----17.3---39.0---278
08-09-11---5150---160.1---10.053---3.979---40.00---15.9----16.3---34.7---283
08-11-11---5258---108.2---06.568---3.959---26.00---16.5----16.4---34.5---285
08-13-11---5375---116.8---07.310---3.899---28.50---16.0----16.9---36.3---284
08-19-11---5563---188.0---12.054---3.899---47.00---15.6----15.8---32.3---263
08-23-11---5731---168.5---10.662---3.939---42.00---15.8----16.1---33.4---276
09-06-11---5948---217.0---14.666---4.159---61.00---14.8----16.0---33.8---287
09-13-11---6176---228.1---15.704---4.139---65.00---14.5----15.5---32.6---282
09-19-11---6352---175.4---11.717---4.139---48.50---15.0----15.6---31.4---275
09-24-11---6582---229.6---13.730---4.079---56.00---16.7----15.8---31.9---299
09-27-11---6755---173.5---11.141---4.039---45.00---15.6----16.0---31.9---284
10-02-11---6921---165.7---11.501---4.039---46.45---14.4----14.9---27.5---265
10-02-11---6921---165.7---11.501---4.039---46.45---14.4----14.9---27.5---265
10-10-11---7063---142.0---10.753---3.999---43.00---13.2----13.7---23.9---256
10-18-11---7277---214.0---13.661---4.099---56.00---15.7----15.2---28.8---275
10-24-11---7401---124.3---09.362---4.059---38.00---13.3----13.9---23.7---241
10-27-11---7563---161.1---10.347---4.059---42.00---15.6----15.7---30.9---283
10-31-11---7715---152.1---10.051---4.079---41.00---15.2----15.2---29.8---282
11-05-11---7894---179.8---13.057---4.059---53.00---13.8----14.7---26.5---250
11-10-11---8047---179.8---10.051---4.079---41.00---15.2----15.0---28.3---271
11-17-11---8138---090.7---07.251---3.999---29.00---12.5----12.7---20.8---223
11-26-11---8274---135.9---11.086---3.879---43.00---12.3----12.6---20.5---227
12-02-11---8401---126.5---09.070---3.859---35.00---13.9----14.3---26.5---228
12-11-11---8492---091.6---08.024---3.739---30.00---11.4----11.7---18.9---212
12-16-11---8588---095.3---07.755---3.739---29.00---12.3----12.3---20.1---213
12-20-11---8710---122.6---09.018---3.699---33.86---13.6----13.8---24.2---234


---date------miles---miles------gals-----price----cost----ampg--cmpg.--spd---range

12-27-11---8838---128.1---09.483---3.859---36.59---13.5----13.8---25.4---265
12-30-11---8949---110.8---07.966---3.899---31.06---13.9----14.1---26.5---237
01-07-12---9107---157.7---11.234---3.939---44.25---14.0----14.4---27.7---237

shchow
01-08-12, 09:57 PM
You should take it in, check the tune or something. I drive the same, mix of hwy and local. I don't beat up my car but I drive it like it wants to be driven.

I calculate my MPG.
Whenever I fill my tank, I zero my trip odometer.
The next time I fill my tank, I divide the number miles driven on the trip odometer by the number of gallons it took to fill it up again.
Seems about right.
I used to get about 11 mpg in my E60 M5...

DrVolkl
01-09-12, 01:47 AM
I drive a mixture of highway and local traffic and I average 12mpg, and that is driving rather sedately.
Any spirited driving and I'm averaging 10mpg or less.
So 16mpg is pretty darn good...

Yeah, I have 1176 miles on my CTS-V wagon... I just got 13.2 on my last tank. I do drive mostly city and I do romp on it here and there... but most of the time I drive pretty mellow. My '99 pathfinder is getting around 17mpg and my 2010 S4 was getting about 18.5. So yeah, this car is a bit behind.

I use Fuelly.com
http://mefi.us/images/fuelly/sig-us/100932.png (http://www.fuelly.com/driver/DrVolkl/cts)

Cub Cadet
01-09-12, 10:50 AM
This is one flaw with doing the "calculated mpg" by hand. The issue is how do you know when the tank is full filling by hand? Is it full when the pump clicks off, or is it full when you squeak another 1/2 gallon in, or maybe an extra gallon? This is a subjective thing that can throw your "calculated mpg" off. For me, I rely strictly on the computer to do this for me since it calculates it live. I re-set the MPG calculator on the dash (I use the AVG MPG) at each fill up and monitor what that reads as I drive through the tank of gas. I watch this all the time... I actually have not looked at the odometer in quite some time since I pay attention to just this screen. I am averaging 19.2 mpg with the winter gas and the cold temps here in Ohio. Once the summer gas and warm temps come back, I will be back up to my 21/22 average. On a good tank where I set the cruise at 66mph and let it go, I can be at 23/24 easily.
Again, I understand that people rely on hand calculations, but it is just an estimate since a full tank to someone is not what it means to someone else. I trust the computer in the car much better.

WhoseCadillacIsThat
01-09-12, 11:14 AM
This is one flaw with doing the "calculated mpg" by hand. The issue is how do you know when the tank is full filling by hand? Is it full when the pump clicks off, or is it full when you squeak another 1/2 gallon in, or maybe an extra gallon? This is a subjective thing that can throw your "calculated mpg" off. For me, I rely strictly on the computer to do this for me since it calculates it live. I re-set the MPG calculator on the dash (I use the AVG MPG) at each fill up and monitor what that reads as I drive through the tank of gas. I watch this all the time... I actually have not looked at the odometer in quite some time since I pay attention to just this screen. I am averaging 19.2 mpg with the winter gas and the cold temps here in Ohio. Once the summer gas and warm temps come back, I will be back up to my 21/22 average. On a good tank where I set the cruise at 66mph and let it go, I can be at 23/24 easily.
Again, I understand that people rely on hand calculations, but it is just an estimate since a full tank to someone is not what it means to someone else. I trust the computer in the car much better.

Good points....We have been using the car's 'instantaneous mileage' display to get a feel for this 'V' and it has had a very influential effect on overall driving habits. As far as 'Average Miles Per Gallon' we are at 15.1 but that is the absolute total from new. The 'Avg MPG' readout is clear-able? It makes sense that it would be.... Learning more about the car almost daily!

We're certain that a Dodge Charger who wanted to get frisky from a stop light last night will remember what the back of a 'V' looks like! There went some mileage!!!! It's all too easy to tromp cars like that....

M5eater
01-09-12, 12:02 PM
This is one flaw with doing the "calculated mpg" by hand. The issue is how do you know when the tank is full filling by hand? Is it full when the pump clicks off, or is it full when you squeak another 1/2 gallon in, or maybe an extra gallon? This is a subjective thing that can throw your "calculated mpg" off. For me, I rely strictly on the computer to do this for me since it calculates it live. I re-set the MPG calculator on the dash (I use the AVG MPG) at each fill up and monitor what that reads as I drive through the tank of gas. I watch this all the time... I actually have not looked at the odometer in quite some time since I pay attention to just this screen. I am averaging 19.2 mpg with the winter gas and the cold temps here in Ohio. Once the summer gas and warm temps come back, I will be back up to my 21/22 average. On a good tank where I set the cruise at 66mph and let it go, I can be at 23/24 easily.
Again, I understand that people rely on hand calculations, but it is just an estimate since a full tank to someone is not what it means to someone else. I trust the computer in the car much better.

gasoline nozzles have a small hole at the end that becomes blocked when gasoline rises to the top of the tank. Once this happens, the pressure drops inside a valve system built into the pump. This cuts off the gas flow. As long as you're at a fuel station that's geographicly on a level surface (which most are because the tanks are built under-ground) you're getting a constant fill-point every time. Past the first 'shut-off' you're trying to by-pass that system and attempt to fill it even more. Not having the neck fully seated will also disrput the results marginally, but it's less than 1/4 of a gallon or so, which even for MPG caculation purposes is only relative to tenth , maybe 2.

cvs
01-09-12, 12:12 PM
Does anyone know how the lifetime MPG is calculated on the OnStar iPhone app? It's located at the bottom of the home screen. Mine reads 16 MPG, which seems a little high based on the average displayed in the car.

Gary Wells
01-09-12, 01:45 PM
I have tried both methods, and the chart that I posted should show you which is more correct and / or accurate.
I generally consider a tank full when it will only take a few more cents between automatic pump stops, however accuracy suffers doing the Cad V this way, even though it seems to work fine on my '87 turbo Buick and also on my '02 Z06 vette that i used to own.
On the Cad v, I almost always use the same pump, head the car in the same direction, and let the slow fill do it's automatic shut-off thing. I do not add fuel from there. Very hard to do consistently on the V.
Look at me chart above, why is the actual mpg always less than the computer? That should tell you which method is more accurate. The computer is generally not off by more than a few tenths, but upon occasion it would be very far off when going past the automatic shut off.
I have never heard of any of the V2's on this forum / site getting more that a shade past 22 mpg, and that was strictly long distance traveling at 70 mph.
Differences of MPG between seasons is probably due to one of more of the seasons using oxygenated gas, something that they do in the Republik of Kali and no longer warn you when they are doing it.

deckofficer
01-09-12, 01:53 PM
I haven't reset the mpg computer for over 2000 miles to see what number it will settle on, and that number is 19.1 mpg. Most all of my driving is mountain 2 lane roads changing in elevation from 1800' to 8500'.

undertaker
01-09-12, 10:23 PM
I strive for single digits, if its double I'm not driving the car hard enough.

I have my TDI for being nice in the MPG department.

DPL
01-09-12, 11:11 PM
I got my V back today and was able to give back the loaner base CTS. All I can say is oh my God...I missed my car

CTSV12
01-13-12, 01:05 AM
Average over 18 for overall first 3500 miles. The average for a 1500 mile run from the midwest to Arizona in 22 hours total was almost 20.

Prof
01-13-12, 08:26 AM
My Lingenfelter modified V2 on two trips to our Marathon, FL home (from Wadsworth, IL) averages about 17 mpg (on-board read out) and that is at a pretty high rate of speed with spirited bursts liberally sprinkled in to avoid driver fatigue.

I think that is pretty great...not that it matters to me...it could be 9 mpg and I it would not alter my unbridled enthusiasm for this incredible vehicle!

The ride to and from the Keys has become nearly as attractive as the stay at our vacation home...actually hate it when I have to fly, but commercial flights are another topic altogether!

Have I told you lately that I love my CTS V???

Rockey
01-13-12, 08:48 AM
I got my V back today and was able to give back the loaner base CTS. All I can say is oh my God...I missed my car

I hear you. When I had the dealer replace my supercharger, they gave me a brand new base CTS as a loaner. Although it looks sharp, it felt like it had 4 flat tires and needed to rev to 4k rpm just to keep up with what I was used too. I begged my wife to let me drive her escalade and she could drive "no balls" until I got my car back. Torque is a very good thing.

carterb
01-14-12, 10:34 PM
I have been checking mine since new - now with 1400 miles, I have been averaging 17 mpg overall, including mostly city driving.

ReaperV
01-14-12, 11:58 PM
I'm averaging 12.5-13.00. 60% city/40% highway. Same route my 2011 SS was getting 15.....
I still prefer my V.

Nine Ball
01-15-12, 09:36 AM
We owned an '08 CTS 3.6 DI before the '09 V.

3.6 DI averaged 21.2 mpg mixed commute.
CTS-V averages 17.0 mpg mixed commute.