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I have 2011 cruze 1.4t AT. I took the car on a trip to Iowa it avg only 26mpg! Seems really low, now there are factors which I realize will make it lower. It was about 90 degrees outside and I had the A/C on most the time and set the cruise @ 82mph.

I bought this car for the good highway mileage but when I took my 500hp mustang there same time the year before with about same conditions and averaged 24mpg this just does not seem right.

Has anyone else experienced this?
 

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Well - cruise @ 82mph... But it's not just because of aerodrag or just the speed itself which is where most people on this forum will leap to.

Here is the major problem, it's not just the speed, but at 82 mph the car's turbo is HYPER responsive, due to the RPM (available exhaust energy) and the load (high gear with high wind resistanc). Nearly any change in throttle position is going to make boost, so unless you were COMPLETELY flat, or going down hill both ways you were in boost... A lot.

I had this same issue. I noticed that if I paid more attention to how I was modulating my throttle, I would easily hit about 40 mph at a high rate of speed. But it's just too responsive at that rpm, too easy to make boost.

In a situation like this however, personally an ECO tune or a custom tune from one of the vendors might be able to help you out with this.
 

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I agree. The tune should help with the RPM being as low as possible in each gear since you have an auto.
 

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I have 2011 cruze 1.4t AT. I took the car on a trip to Iowa it avg only 26mpg! Seems really low, now there are factors which I realize will make it lower. It was about 90 degrees outside and I had the A/C on most the time and set the cruise @ 82mph.

The 2011 cruze automatic is geared lower than the 2012. The highway rating changed from 36mpg in 2011 to 38mpg in 2012. That change in gearing helps get better mpg at high speed, but the car still suffers above 75mph. Similar drive as yours cruise set at 75mph I get about 32.5mpg. At 64-68mph I can get 42-37mpg with ac on full.

Think I read on here that the 2011 cars like highway speeds below 65mph for best MPG. also with higher outside temps higher octane gas can sometimes pickup 2-4mpg.

Easiest way to gain MPG is slow down. it might take slightly longer if you slow down, but not much. The difference from 68mph to 72mph is about 4minutes on 150mile drive. I'm sure the difference from 82mph to 78mph is not much different but would probably pick up an easy 2mpg.
 

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75 mph cruise with the AC on in my Eco results in 40-43 mpg. Wind is a factor.
 

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Bunch of things working against you:
1. 2011 automatic - worst Cruze for fuel economy
2. 82 mph - 'nuff said.
3. A/C on full - this A/C system saps power from the car
4. 90*F out running presumably 87 octane - the engine was dumping in LOTS of fuel to prevent pre-detonation in a high-load situation.
5. Wind - depending on direction, you may have been heading into a stiff breeze, effectively causing the car to use fuel like it's going 95-100 mph.

Next time, slow down! The car simply isn't going to get good fuel economy at 82 mph, no matter how much we wish it would. At that speed, I'd be lucky to see 34-35 mpg from my Eco.

And, during the summer when it's above 75*F out, fill the Cruze with premium instead of regular. The fuel economy difference on premium will more than offset the $2-3 per tank price difference.
 

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I did a 130 mile trip Saturday with the cruise set at 80mph. The DIC says 46.8mpg, so probably 42 or so actual MPG. However, I have an Eco MT, and drive at 7000' elevation. Not sure where your RPM is in a non Eco AT, but I'm guessing that you're running pretty high at 82mph.
 

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I drive to cresco a few times a year (WAY NE iowa) and its really quite windy going up there and wide open plains so no wind breaks at all. Eats gas like crazy.
 

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That doesn't sound right. I took about a 1000 mile trip and my average has never been less than 30. I don't reset the mpg anymore.
1.8, AC the whole time, up hill going to San Diego.

Sent from my SGH-T989 using AutoGuide.Com Free App
 

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IIt was about 90 degrees outside and I had the A/C on most the time and set the cruise @ 82mph.
Your not going to get close to the EPA at anything above 70. 82 is just overkill. Cruze suffers with small engine and turbo spooled. I think at 82 mph, the engine is at just over 3000 RPMs. Your making a lot of boost...

I have an '11 as well. I wouldn't recommend going past 70 mph on the highway if you want to get 'decent' fuel economy. Air conditioning doesn't hurt terribly but it certainly does at higher speeds. 65 mph is kind of the upper tier for decent fuel economy in this engine.
 

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I've changed my route to work such that I do not hit the interstate. It adds 3/4 mile to my commute and 2 stoplights that are about a 50/50 hit or miss whether or not I have to stop.
Cutting out that 7 miles of interstate at 60-70mph to avoid becoming roadkill, and replacing it with about the same amount of 2 lane rural roads seems to have upped my mpg, as I'd expected.

I still have just over half a tank of fuel left. My average speed has been dropped to about 33mph (from 36mph - average when taking the interstate).
When I parked this morning, the DIC was estimating 45.2mpg. I've never had this happen.

I'm running 44psi tire pressure, no tune or engine mods yet, 93 octane shell and a light foot.
No A/C this tank, hasn't been that hot.
 
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I've changed my route to work such that I do not hit the interstate. It adds 3/4 mile to my commute and 2 stoplights that are about a 50/50 hit or miss whether or not I have to stop.
Cutting out that 7 miles of interstate at 60-70mph to avoid becoming roadkill, and replacing it with about the same amount of 2 lane rural roads seems to have upped my mpg, as I'd expected.

I still have just over half a tank of fuel left. My average speed has been dropped to about 33mph (from 36mph - average when taking the interstate).
When I parked this morning, the DIC was estimating 45.2mpg. I've never had this happen.

I'm running 44psi tire pressure, no tune or engine mods yet, 93 octane shell and a light foot.
No A/C this tank, hasn't been that hot.
40mpg on regular (87) would probably be cheaper.... though I cant be bothered to do the math.
 

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Your not going to get close to the EPA at anything above 70. 82 is just overkill. Cruze suffers with small engine and turbo spooled. I think at 82 mph, the engine is at just over 3000 RPMs. Your making a lot of boost...
By nature, you're not technically making boost. In order to make boost, exhaust pressure needs to be built. In order to build exhaust pressure, you need to have lots of air going into the cylinders, and in order to have lots of air going into the cylinders, the throttle needs to be opened enough for it to do so. If your throttle is barely cracked a hair open, it will only be able to suck in enough air to keep the turbo turning "slowly" enough to run the motor without building power to accelerate.

At that speed, you're simply creating a lot of boost simply because your car has to overcome much higher aerodynamic force. You create more boost at 2500RPM in 6th gear than you will at 4000RPM in 3th gear at a steady, cruising speed, whatever that speed equates to at that RPM and gear ratio.

To the OP:
Inflate your tires a bit. I'd recommend at least 35psi, preferably 40psi.

Check your spark plug gaps and re-gap them to anywhere between .028 and .035. There's a high enough chance that they're horribly inconsistent to make them worth checking, and something like that will definitely affect your fuel economy. Remember to pull your battery ground cable to re-set the PCM's fuel trims after you do this. Fuel economy gains have been noted in the 1-3mpg range after this adjustment.

If it's hot out, pump 89 or 93 octane fuel, but not 87 octane.
 

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Just as another data point I drove a 2,000 mile trip last summer in my 1.8 LS with manual trans. It was 100 deg. the whole way with the A/C on and I got 36 mpg with the cruise set on 74. Maybe the brakes are dragging on the OP's car.
 

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Just did the math and it saves you about 2 cents a mile to use premium over regular, with the current heat wave going on anyway.

8c / mile versus 10 cents.
Not sure if I understand what you're trying to say. Can you elaborate?
 

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Not sure if I understand what you're trying to say. Can you elaborate?
roughly (very roughly) going off the DIC reading of 45 something mpg which i know is at best optimistic a few mpg and using my one calculated tank.

divided the price per gallon by the mpgs gives me roughly the cost per mile in cents. Its not a great way to do it but im at work and quick and dirty + small sample size on my part.

price per mile
3.33 / gallon regular
3.62 / gallon premium (where i live anyway)

3.33/31.2mpg = .10c a mile
3.63/45.x = .08c a mile.

Best price/performance would probably be midgrade 89.

unless i royally screwed up the math which is possible....errr likely.


Once I get a few more fuel ups in my 1LT ill try midgrade for a few tanks then premium for a few tanks and see what happens.
 
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