Fuel Economy and Air Conditioning

[Brian]

To the OP, I get very similar MPG in a '10 sedan. 50-60 MPH mileage it goes up quite a bit, temp and traffic impact things a lot, also hills. I get 27.5-32 depending on the above driving around 75 MPH most of the time on cruise and I have a A/T. Usually normal freeway commute with AC is 29MPG. Cool but not cold weather helped MPG by about 2 MPG after the winter. I commute 128 miles 95% freeway everyday. Very consistent MPG regardless.

[RiderOnTheStorm]

To the OP, I get very similar MPG in a '10 sedan. 50-60 MPH mileage it goes up quite a bit, temp and traffic impact things a lot, also hills. I get 27.5-32 depending on the above driving around 75 MPH most of the time on cruise and I have a A/T. Usually normal freeway commute with AC is 29MPG. Cool but not cold weather helped MPG by about 2 MPG after the winter. I commute 128 miles 95% freeway everyday. Very consistent MPG regardless.

Thanks Brian! I appreciate that information. It looks like my mileage is consistent than for that speed with A/C and cruise. I will just have to learn to go slower and I will certainly be waiting for it to cool down so I can dump the A/C...

[paulsaveo]

Your milage sounds fairly close to mine so I feel a bit better seeing that - thank you! What speeds are you typically driving?

mostly city, around where I am 45 to 55 mph, last october I took my 2 yr old daughter to San Antonio, from where we live its all highway, a straight shot on the highway for 5 hours at 70-75mph I actually got 37mph with a/c used a little here and there on the drive. a few months ago we (my wife, daughter, and my self) took a 12 hour drive to new orleans in my wifes 09 corolla, the best I could get in the corolla was 33mpg that was at 3am on I-10, so there was no traffic, not using a/c had cruise set at 65mph

[Thymeclock]

Its nothing that I have gone into researching.............its just something that I have heard as well. When I would get a new car it wasnt to save gas so I wouldnt check to see what my MPG was and when I bought this car (to save gas) it was used. I do remember there being some rumors about engine shavings and impurities in the oil for a new engine but I dont know if that affected MPG or if it is even true( again I dont care enough to go do some scientific research) to begin with. BTW do yoou have any info other than your experience that confirms that this "myth" is just that or do you just say this casually?

I log all my MPG on all of my cars (3) with every fill-up, so I have a continual record of it for the entire life of each vehicle, and I've been doing this for 40 years. I typically will own a car for more than 20 years, as each one is only driven about 5000 miles per year. I've never seen any improvement in MPG in any of my cars as they got older, and most were bought new. (I currently have cars that are an '89, a '99 and the '09 Aveo.)

Since there is no proof that this is anything other than a myth, it deserves to be called that. Also the idea that MPG would increase flies in the face of logic. The only difference between a vehicle when it is new compared to when it is old is the amount of wear it has on it. I don't see any way in which increased wear is going to improve MPG at all.

[petrified.rabbit]

i think the "myth" started with poor manufacture standards, as cars in the past have been delivered with unseated rings.. it would take 100 miles or so for the to seat, and if seated properly, an oil change and then the "improvement" while running/driving.

But that is ancient history. Even though some manuals say otherwise, most engines are started and rings are seated by the time they leave the factory today.

i myself see improved gas mileage in summer, summer fuel is much better than winter fuel. but also on cooler days, as stated. plus some brands of gas are much better than others for mpg.. so keep that in mind. Although i am not a fanatic like Thyme...

[RiderOnTheStorm]

i myself see improved gas mileage in summer, summer fuel is much better than winter fuel. but also on cooler days, as stated. plus some brands of gas are much better than others for mpg.. so keep that in mind. Although i am not a fanatic like Thyme...

Isn't the difference in summer mileage and winter mileage more attributed to temperature? I am not trying to challenge you, especially since you're quite the expert and I'm the small fry here But I thought temperature extremes, especially cold plays havoc with mpg.

Also what fuel do use or recommend? I used to use BP prior to buying this car, but since GM recommends "Top Tier" fuels and there is a Shell close to my home, I use that.

[petrified.rabbit]

i have the best luck with bp and sunoco.

temperature does have a lot to do with mileage. but even when it is warm still but winter fuel is still in the pumps, MY aveo gets 270-280 mile per tank, instead of the 300-320 it gets with similar temperatures and driving when i know it is summer blend.

disclaimer: i loose the same amount of mpg with sheetz and getgo gas (two local popular discount brands), regardless of time of year. we do not have a shell locally, but one is opening, i am interested in seeing the resulting mileage.

[subachad]

My Aveo ran a lot better after 1000 miles. Then again, I also had opened up the airbox and swapped out the rear muffler by then too which not only helped power, but MPG as well.

With my scanner plugged in, I get an "immediate MPG" result of about 47MPG at 70MPH. Thats probably high but for the purpose of this test I was only testing against myself. Turning on my A/C would drop it to 33, this was done over a 17 mile stretch of highway multiple times on multiple days with the same result.

I should also point out I have a hatch so fuel economy takes a big hit at speeds above 70mph

chad
Unique Motorsports - Mostly cars, some info regarding installs, some tech, some around the house upgrades, and a few other random ramblings.

[timmytaxi]

Does anyone know what the plug is called that is on the coolant line that triggers the compressor to come on? My cold air intake was sitting on the plug and it cut come wires .

[timmytaxi]

cycling switch?