Fuel Economy and Air Conditioning

[redrob]

If its new thats part of the issue, new cars need to be "broken in" first then the MPG starts to climb. It is difficult to say how long before you will see an increase in MPG but running the A/C has little effect on overall MPG. The big thing is the speed your driving at( 65, 75, 85mph) and you will see your MPG drop significantly. Also dropping the added weight will also help improve your MPG. All in all your new car will not get your EPA estimated MPG at the begining. I have an 08 hatch (auto running A/C) I get about 315 miles out of the tank so I still need to figure it out but its around 28-30mpg at 65-75 with big elevation changes.

[Thymeclock]

If its new thats part of the issue, new cars need to be "broken in" first then the MPG starts to climb.

I've heard this nonsense repeated before, but never is there any proof offered. It sounds like something a dealer would say to get you to go away and stop complaining. Please explain how and when this magical event of "then the MPG starts to climb" is supposed to occur.

[Thymeclock]

My test, conducted using a ScanGauge when the car was still practically new, recorded 37 MPG @ 65 MPH with the A/C on, on a level highway, determined over a 20 mile trip. As soon as the speeds are lower than 50 MPH (owing to the A/T not being in lockup mode) the MPG drops enormously.

This car gets wonderful MPG if you can always drive exclusively at highway speeds of over 50 MPH and avoid all other types of driving.

And as for the "broken in" myth, now that my car has 8000 miles on it the MPG is still the same as the day it was bought new.

[redrob]

I've heard this nonsense repeated before, but never is there any proof offered. It sounds like something a dealer would say to get you to go away and stop complaining. Please explain how and when this magical event of "then the MPG starts to climb" is supposed to occur.

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?

[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.

[gonecg]

A/C and mileage concerns.
I have over 127K on my 2005 Aveo with automatic and it still runs pretty well. I keep meticulous records on ALL my cars. I have gotten as low as 25.2 mpg around town with AC on to 29.6 mpg as the high. Our temps here has been 99 to 112 degrees this last six weeks so I run the AC a lot. My road mileage has been 32.1 to 38.3. I drive on the roads, no interstate, @ 60 to 65 mph. If I would drive 55 to 60 maybe I would get near 40mph. I do feel that the AC might take off some mpg, maybe 2 ? Very happy with my MPG

[Chevy Customer Svc]

A/C and mileage concerns.
I have over 127K on my 2005 Aveo with automatic and it still runs pretty well. I keep meticulous records on ALL my cars. I have gotten as low as 25.2 mpg around town with AC on to 29.6 mpg as the high. Our temps here has been 99 to 112 degrees this last six weeks so I run the AC a lot. My road mileage has been 32.1 to 38.3. I drive on the roads, no interstate, @ 60 to 65 mph. If I would drive 55 to 60 maybe I would get near 40mph. I do feel that the AC might take off some mpg, maybe 2 ? Very happy with my MPG

Hi cameraguy,

Thank you for your post. Glad to hear you're still reaping the benefits of great MPG with your Aveo at its current mileage and Aveo still is giving you good service. If you have any further questions or concerns, please post.

Vanessa
GM Customer Service