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Discussion Starter · #1 ·
All winter long my average gas mileage has been 12mpg. It would vary between 11.9 to 12.2. Since my last 2 fillups of Shell 93 I jumped to 14mpg. I haven't changed my driving at all. I live 5 miles from work and drive fast all the time. Could the gas stations have changed to a summer blend, or am I just crazy. I've got about 8,500 miles on it and its an 04.
 

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I don't understand how you guys get such ****ty gas mileage, I don't baby my car and avg 18-20

lowest was 16.3 and that was after a few passes at the track

highest was 24.8
 

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C5ORGTO said:
All winter long my average gas mileage has been 12mpg. It would vary between 11.9 to 12.2. Since my last 2 fillups of Shell 93 I jumped to 14mpg. I haven't changed my driving at all. I live 5 miles from work and drive fast all the time. Could the gas stations have changed to a summer blend, or am I just crazy. I've got about 8,500 miles on it and its an 04.
The hotter it is, the more efficient the engine runs, as a rule (and to a point).

I would be interested to know if the guys that put the cooler thermostat in have seen a drop in mileage as well.
 

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My average is 16-18. I reset every month to get a feel for it. I have a pretty even balance of street and freeway driving.
 

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Are you guys going by what is diplayed on the DIC for your gas milage? I have noticed that it is not too accurate. When I first got my 05 I noticed about a 2 or 3 mpg difference. I average between 15 and 16 mpg when I figure it by hand.
 

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8500 Miles on the car the very best all interstate from fort worth texas to tulsa ok in january very little wind set cruise at 75 up to tulsa averaged 18.9 none stop except for fuel just before tulsa which is a little over 300 miles. next day home drove the piss out of it anywhere from 75 to 110 and made 21.3. most of the time city driving get anywhere from 13.5 to 17 (SUCKS) my 7000lb diesel will do that o yea by the way the car was bone stock put exhaust, cai, and diablo on since runs better but same mileage.:confused :confused
 

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jortegasr said:
Are you guys going by what is diplayed on the DIC for your gas milage? I have noticed that it is not too accurate. When I first got my 05 I noticed about a 2 or 3 mpg difference. I average between 15 and 16 mpg when I figure it by hand.

i've done the calculations, my unit is pretty dead accurate, sometimes off a few tenths
 

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To answer your question of Why?? your gas mileage improved. No you did nothing !!! The answer is it's getting warmer. Engines use ( need ) much more fuel during warm-up to normal operating temps in cold weather. Yes, effieciency improves only so far as warm oil has less friction than cold oil. But once the engine and OIL are up to normal operating temps, the difference between Warm and Cold ambient is not as great of an effect on fuel economy as simple start up engine temperature. Cold fuel enrichment is the main difference between summer and winter fuel economy. Engines stay in an enriched state ( not only richer BUT RICHER LONGER ) as the temerature goes lower. That is the primary reason you get better fuel economy in the Summer vs. Winter.
 

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Discussion Starter · #12 · (Edited)
Thanks all. I thought it might have something to do with getting warmer. Its only up to 50 Degrees, but it is warmer. I thought I was going to be stuck at 12mpg forever. I live so close to work too(5 miles), I'm only on the highway for a short time, and those full throttle 0-60 runs don't help either. I was getting 16.5mpg in my Vette, so when I saw 12mpg on the GTO, I was a little bummed. (Yes the Vette is 500lbs lighter, and more aerodynamic, which is why it got better gas mileage).
 

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Live in FL and have pretty consistent gas mielage winter or summer.

My question is: Did anyone with a CAI notice a substantial increase in MPG when they installed their CAI? I go by the miles driven on a full tank in normal city-ish driving. Where I was getting 170-190 per tank before the CAI, I am now getting 210-230 miles. Been about 4 weeks and it's been consistent.

That's about a 1-3.5 mpg difference. Anyone else wanna help me hijack this thread? :D
 

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MeanGoat said:
Live in FL and have pretty consistent gas mielage winter or summer.

My question is: Did anyone with a CAI notice a substantial increase in MPG when they installed their CAI? I go by the miles driven on a full tank in normal city-ish driving. Where I was getting 170-190 per tank before the CAI, I am now getting 210-230 miles. Been about 4 weeks and it's been consistent.

That's about a 1-3.5 mpg difference. Anyone else wanna help me hijack this thread? :D
I do all city driving in Orlando traffic...I get about 230-240 per tank full. I'm still stock, no CAI.
 

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According to my wallet, my MPG reading is dead on accurate. :willy:

I’ve come to the conclusion that, short of securing a surrogate driver, I’m stuck at :eek: 15. I’m thinking of putting a brick under the gas pedal. That should help my MPG.
 

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GOATGIRL said:
I'm like you...getting the same 230-250 here in Jacksonville...I'm still stock too.
Don't get me wrong, my dash says I'll get 250-260, but in reality when I check the trip it's what I stated earlier. I must admit that I am a rabid fan of the "take off as hard as the tires can still hold" methodology of driving. :D
 

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I haven't had mine long, but I have been driving it like an old lady. I did notice that when I started "enjoying" the car, it seemed to improve. I am going to raise the RPM limit during my commute and see what happens; but not against the T/C limits.
 
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