I have a 2009 (2LT) 2.4 Flexfuel New to me and going on a trip in a few weeks.
Ive always used Regular ( and I will be adding seafoam to the tank and doing a full tune up before the trip. Which gas gets better MPG ? The highway speeds here are 65-70 and will be on the highways for most of the trip 200+ miles and then back roads ranging from 45-60 for about 50-75 miles to desination. Since yhis is a flexfuel it is new to me and just wondered. The HHR has 145K on it and runs great, xmooth. Thanks for the input on this

 

Burn the cheapest it calls for. You can not gain a thing by burning higher.

 

Not true, fuels are blended for better combustion ( higher octane,- less pinging and more through combustion ) Better combustion results in less fuel and more power as to why engines are tuned to specific fuels ( gas, alcohol, ethanol...ect... along with their octane ratings ) so if other fuels are used instead , it lags in performance . From what I have read on fuel related sites, it says E85 and other such E fuels suck , lacks perfomance and really drops the mpg's. since the HHR is a flex fuel, I wondered how it does on the E fuels before I even try it since we are taking a long trip, wanted first hand input from others who has experienced the flex fuel otherwise I will stick to my cheaper 87 or 89 octane.

some issues Ive read with flex fuels is harder starting, less mpg, higher costs, so just wondered about it since Ive never used flex fuels before.

 

Precisely why I haven’t used E85 when on a trip, I stick with what I know and I know my HHR runs great on 87 octane.

 

Alcohol has a higher energy lower MPG. You have to do math to figure your economy, just like the choice between 100 Octane and 83 Octane. Yes, higher Octane gets better MPG, but is the cost per mile better? Sometimes, depends on price.

 

I felt forced to do a bit of lurnin’ about E85 because my 2011 2.2 decided she had a bunch of ethanol in her tank even tho she didn’t, and made a fuss.

I would would strongly favor E85 when it’s about 1/3 cheaper, i.e., $3.00 vs. $4.50, for example. The difference in fuel consumption isn’t as simple as BTU content. An IC engine optimized for ethanol is substantially more efficient than one optimized for gasoline. It’s also (arguably) renewable, also burns cleaner; better for the motor, better for the environment.

Be aware that “E85” no longer means 85% ethanol. It means 51-84% ethanol. Retailers in cold climates are supposed to sell E85 with less ethanol is the Winter because some FlexFuel cars can be hard to start on 84% when it’s very cold. But it can “legally” be 51-84% any time of the year. And they don’ need to tell you the %, and may not know. Once you have some experience with E85 in your car, you can decide how much cheaper it needs to be to work for you, but without knowing the actual % you’re buying it’s a bit of a guess. If you assume you’re getting 84% and it’s really less, that’s money in your pocket.

You should always turn off the car when fueling, but it becomes extremely important when switch to or from E85. That step is needed for the car to figure out how much ethanol is in the fuel it needs to burn. The car has no ethanol sensor, per se.

I don’t get to use E85 much because only one place sells it here and when it’s cheaper it’s not by much.

 

agreed, Just dont know what the differences in mpg and costs are yet

 

Thats what I read.... only 3300 stations across the US carries it.....

 

BTW the 2011 manual (my year) says premium 91 fuel is preferred for the 2.4 and regular 87 is fine for the 2.2. The same goes for 2010, but boy was I surprised when I had a look at the 2009 manual on line. Basically, the opposite is true! So officially, your 2LT w/ 2.4 is just fine with regular 87.

Obviously, if you have a 2010/11 2.4 that prefers 91, the potential cost savings of E85 is even greater.

 

I did not get a paper 2011 owners manual, just the online in Donbrew’s sig.