Hi, where I am living is really hot in summer. I usually turn on the maximum AC when I drive, which is "4". I don't know why I find the gas bars (meters) drops fast. For example, let's say one bar can let me drive 25 -30 miles, but now only half distance like ~15 or even less. I don't know if this is normal? Anyone has the same problem as mine? Or I need find a someone to look at my AC.
AC uses a lot of Gas?
- Thread starter sdpapet
- Start date
Italianjoe1
Member
Can't measure it like that. Gotta average your actual mileage based on fill ups and miles driven.
Yes the a/c makes a big difference in this car. The engine is small and has to work harder to turn the compressor, so you notice it.
Yes the a/c makes a big difference in this car. The engine is small and has to work harder to turn the compressor, so you notice it.
Coolbreezin
Member
As long as I stay in the 30mpg range Im happy. I sold my 1992 Metro which got 50mpg. So its a hard adjustment.
How about Gas? Do you use a lot of gas if you turn the AC on? "The compressor" you mean the AC compressor? I haven't notice any problems about AC affecting engine or car performance. I drive automatic car, but I feel AC is a gas eater.
My friend drives a large SUV, but I don't think her AC uses a lot of gas.
Papasonic
Active member
Yes, gas mileage on any vehicle with a small displacement engine will suffer when using the AC. Also wind and hilly conditions are detrimental to fuel economy. A larger vehicle with a V8 engine isn't affected as much by using the AC, as horsepower and torque are in abundance. Small vehicles with small engines have wildly varying fuel economy, depending on operating conditions. On my Silverado and GTO; I don't notice the fuel mileage vary significantly using the AC, nor do I feel much performance difference.
Oh, the total horse power of my car is around 140. Hmm, it shouldn't use so much gas.
Maddmatts
Member
Your engine isn't producing 140 HP all the time. That's it's maximum output
The following is an example only. Actual numbers will probably vary:
Your engine might only need to produce 20 HP to maintain a speed of 30 mph. That 3 HP drain now requires the engine to produce 23 HP to keep going that same speed.
That's a 15% increase in power demand, creating the same increase in fuel consumption.
The Champ
New member
Fuel mileage varies so much by the way you drive and the traffic of the day.
On the highway, staying close to the speed limits and maintaining a steady speed, you will get nearly the same fuel mileage using the AC as you will driving with the windows down (aerodynamic drag by having the windows open will hurt the mileage about the same as having the air on).
In town, stop light to stop light in heavy stop and go traffic, the AC will have a much more dramatic impact on fuel mileage.
I'm glad that I live in a rural area and it doesn't cost me any more to be comfortable when I drive.
I also rarely run my AC at anything more than position 1 or 2 for any length of time. I might put it on 4 to do a rapid cool down when I first get in - but that's just for 2 - 3 minutes.
On the highway, staying close to the speed limits and maintaining a steady speed, you will get nearly the same fuel mileage using the AC as you will driving with the windows down (aerodynamic drag by having the windows open will hurt the mileage about the same as having the air on).
In town, stop light to stop light in heavy stop and go traffic, the AC will have a much more dramatic impact on fuel mileage.
I'm glad that I live in a rural area and it doesn't cost me any more to be comfortable when I drive.
I also rarely run my AC at anything more than position 1 or 2 for any length of time. I might put it on 4 to do a rapid cool down when I first get in - but that's just for 2 - 3 minutes.
I am driving in the town. It is short distance drive most of time (10 miles round trip). The traffic is not too bad, but the gas is kind of doubled if I turn on the AC.
The Champ
New member
Very short trips are the worst case scenario for trying to get good fuel economy. Adding the use of AC in this situation only makes it worse.
JTee2017
Well-known member
I'm ok with the MPG so far on our new 2017 Sonic RS Hatchback 1.8L auto trans.
About 550 miles now and only on second fill up. We did some city driving on the first tank and also took it on a couple of short 75 to 150 mile state highway with some interstate jaunts and DIC showed 35.4MPG and up to 38 for awhile. When I filled up it hand calculated for the first tank 34.8 MPG.
Drove around town most of 10 days and DIC showed between 27 and 28MPG.
This second tank full is more city driving and showing 28.4 MPG.
All of these are with A/C on most of the time since it has been in the upper 80's to 90's the past 10 days or so.
About 550 miles now and only on second fill up. We did some city driving on the first tank and also took it on a couple of short 75 to 150 mile state highway with some interstate jaunts and DIC showed 35.4MPG and up to 38 for awhile. When I filled up it hand calculated for the first tank 34.8 MPG.
Drove around town most of 10 days and DIC showed between 27 and 28MPG.
This second tank full is more city driving and showing 28.4 MPG.
All of these are with A/C on most of the time since it has been in the upper 80's to 90's the past 10 days or so.
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5.0
Member
The variation in fuel mileage for this car is quite extreme. This thing can be an absolute pig in the wrong conditions.
I have gotten as much as 46 mpg on the highway, in moderate weather, doing the speed limit(100kph), no A/C. Premium fuel.
A recent trip travelling 370 km, 95% highway, during 40* weather, A/C running, doing the speed limit (100kph), I only netted 29.5 mpg. Premium fuel.
Funny thing is, my Corvette in 40* weather,travelling 420 km, 95% highway, no A/C, doing between 120 kph-160 kph I got 30mpg. Yep, my corvette can achieve better fuel mileage going faster.
I have gotten as much as 46 mpg on the highway, in moderate weather, doing the speed limit(100kph), no A/C. Premium fuel.
A recent trip travelling 370 km, 95% highway, during 40* weather, A/C running, doing the speed limit (100kph), I only netted 29.5 mpg. Premium fuel.
Funny thing is, my Corvette in 40* weather,travelling 420 km, 95% highway, no A/C, doing between 120 kph-160 kph I got 30mpg. Yep, my corvette can achieve better fuel mileage going faster.
What you said is exactly I described. YOur Corvette is 5.7 L engine? right? My sonic is 1.8L. Whenever I turn on the AC, the mileage per gallon decreases significantly. I know small engine has this kind of problem, but AC shouldn't cause so much gas. I kind of think if this is Sonic engine designing bugs?
Has anyone driven other brand of eco-cars like Versa? Does it have the same problem?
Has anyone driven other brand of eco-cars like Versa? Does it have the same problem?
5.0
Member
Yes it's 5.7L.
Any car with A/C loses gas mileage from the compressor turning on. I think it's just more pronounced in smaller engine vehicles because the engine has to work much harder than a V8 to turn the compressor.
There is more to it than just the A/C as well. The Corvette is a very efficient design. It has a lower drag co-efficient, longer 6th gear, is fairly light (3200 lbs) and has a engine is more powerful and doesn't have to work as hard. The longer 6th gear makes a big difference. At 160kph it's turning 2000rpm, where the sonic is turning 2000 rpm at 100kph.
