[michael]

I have been reading all of the internet, mostly on this forum, over the debate of filling up the Cruze with the highest octane fuel. I have had my 2012 Cruze LS 1.8L since December of 2011. Until the last two times I have filled up(past 3 years), I have used regular gasoline. But recently, I was told I need a fuel injection cleaning and told that if I simply put in a bottle of fuel cleaner as well as use Shell V-Power, that would do the trick.

I did do that and the two times I have done it, I have noticed much better performance out of my car. Not only better performance, but better millage too. I did read in the Cruze manual and it states about using at least regular unleaded fuel (87 Octane level). But the manual states you can use higher octane if you wish.

Everyone I have spoke to about this thinks, "it's a bad idea", "it's not good for your engine". Both people who know cars and others that have just had more experience with cars.

I don't see what can be the downside to using higher octane gas in the Cruze.

What are your thoughts? I am stuck with what to believe.

 

[iTz SADISTIK]

I'm 29, ever since I was 15 I've used 93 in all my engines. (Chevy S-10, Silverado, Equinox,Cavalier/Pontiac G-6, Infiniti G35, Ford Focus) I have never had an issue.

 

[BowtieGuy]

I'm not sure about the 1.8, but the 1.4T definitely responds to increased octanes in terms of performance and MPG. But in colder weather, the effect of increased octance is less noticable. At least that has been my experience so far.

I use the following criteria based on average temperatures for the upcoming week to determine which octane I use:
-Below ~65-70 degrees F, 87 octane
-From ~70-80 degrees F, 89 octane
-Above 80 degrees F, 91/93 octane

These criteria give me the best combination of performance (or also lack of timing pull under load in hot weather and with A/C use) and cost. As always, YMMV.

As a further note, this is the first vehicle I have used anything other than regular 87 octane, and that was after extensive research into the affects of octane on this specific engine. For most N/A vehicles, I would just stick with 87. But it all depends on the specific engine/application.

 

[Dragonsys]

it is not bad for the engine. But with a NA engine, just try it out as your results will vary. Run at least 2 full tanks before you make a decision though.

 

[spacedout]

I have always gotten slightly better mpg with premium in all the cars I have driven. Most you would notice little or no difference in power.

 

[Eddy Cruze]

I'm using 91 because 93 isn't sold here and I saw the video from the GM VP talking about the need for Premium fuel in the Turbo CRUZE. I was also told the CRUZE would run cooler and its been 115 this Week, cooling down to 86 at night. I cracked my last tiny engine out here in the heat and this one is even smaller?

 

[Abrunet85]

I use whichever one has no ethanol in it. Around here it depends on the station you go to, some are 91 that have no ethanol and some are 93 that have no ethanol. I just got rid of my Cruze, which was the LS 1.8, and I've noticed it runs 1l/100km less (6 MPG better) than regular gas, which around here contains 10% ethanol. I had been doing this for the past two year, with no problems. We still have my wife's Cruze, a LT 1.4T, and she's been doing the same.

 

[spacedout]

I'm using 91 because 93 isn't sold here and I saw the video from the GM VP talking about the need for Premium fuel in the Turbo CRUZE. I was also told the CRUZE would run cooler and its been 115 this Week, cooling down to 86 at night. I cracked my last tiny engine out here in the heat and this one is even smaller?

With those temperatures Eddy its really a shame you can't find some 93 octane fuel anywhere. Doing octane/ethanol content testing I found 91E0(no ethanol) performance was poor anything above 82F outside. Switching to 93E10 I have much better power below 2500rpm in the 82-100F temps I have seen with the cruze.

I don't know if your temps are humid, mine certainly are so that could also be a factor. Not sure if humidity has any effect on engine performance though.

I would keep looking around for a station with higher octane, 99% of the stations here all carry 91 octane as premium, however once I started looking I started finding a few different brands that carry 93 octane. Heck I can go to a Shell, BP or mobil in one city and get 91 octane, but the next town over has 93 octane, so it doesn't hurt to check the same brands too.

 

[Eddy Cruze]

I think there is Sunoco racing fuel available which is 95 octane, thought it was 103 octane but its $7.19 a gallon. the problem I have out here and no it is not humid is the cost factor between 87, 89, and 91. 91 is 40 cents more a gallon, that's a lot as the grade difference used to be less than a dime in the old days. 2001 was a great year, 99 cent Gas and that was after the TERROR!

 

[BowtieGuy]

I think there is Sunoco racing fuel available which is 95 octane, thought it was 103 octane but its $7.19 a gallon. the problem I have out here and no it is not humid is the cost factor between 87, 89, and 91. 91 is 40 cents more a gallon, that's a lot as the grade difference used to be less than a dime in the old days. 2001 was a great year, 99 cent Gas and that was after the TERROR!

Mojave, mo problems, amirite? :smileystooges:

 

[jblackburn]

1.8 - does the car feel or perform better with 93 octane over 89? If so, use it. If not, then don't.

The 1.4 definitely responds better in summer temps with higher octane, but there is no difference in the cold.

Our other (non-turbo) car does not respond any better switching from 89 to 93, so there is absolutely no point. It does, however, pull timing and feel sluggish to a small extent on 87 octane. If your Cruze responds in the same way to increased octane, it too has a high-octane fuel map that will allow it to run to its full potential without knock.

 

[Austin9991]

93 octane for the turbo for sure. No other way!

 

[Robby]

To the OP....higher octane ratings will not harm the engine in any way.....so relax.

There can be diminishing returns though.
In the case of the Cruze, it seems either engine design responds favorably to higher octane numbers.
Evidently, there is enouph available ignition advance to take advantage of the higher knock resistance that 91/93 provides and, because it can 'light the fire' a bit sooner in the compression stroke, you can get the same power with a smaller throttle opening.
That, of course, results in the mpg enhancement and a driveability improvement, often described as a peppier or more response to throttle feeling.

We, as a group, have noticed this is particularily noticeable in high heat, high load (A/C operating) around town driving where engine temperatures are at the upper edge of normal.
The engine has a tendency to 'spark knock' under these conditions and the computer retards the ignition timing to prevent mechanical damage.
The operator notices a delay in throttle response and a mileage decrease that disappears when operating with the higher octanes.

My eco auto around town average increases by a bit more than 3 mpg using 93 in the hot summer months as opposed to 87/89 regular.
But, as soon as ambient temperatures are consistantly below 60 degrees (f) I can match the mileage using 87/89 and because the air is cooler the tendency to retard the timing is reduced and driveability improves.

Moral of the story, for me, 93 for best mileage and driveability above 60 degrees.....come fall, back to regular.

The other side of the coin.....one of my many vehicles is a 97 Chevy C-1500 long cab, long box, 350 v-8 auto.
It doesn't care what octane you pour in it......18 to 21 mpg....cold, hot, fast or slow, runs the same hot or cold, air on or not.
It makes it clear that small displacement engines can show big benefits from small changes, larger displacements (both stock) don't.....or at least, rarely measureable.

Rob

 

[obermd]

I use 91 in Denver and 93 where available. I have tested 91 in my son's LS MT and there is a definite improvement in drivability, low end power, and fuel economy.

 

[Merc6]

Some cars like mine hate 87 summer, spring, fall ,and winter. 87 in my car in the winter is even harsh if traction control kicks on. You would swear I had an anti lag tune from all the backfires.


Sent from my iFail 5s

 

[cruze01]

93 for me year round. I've been using it almost since the first tank. With 87 the car is just to unresponsive and the turbo lag is terrible. With 93 the car is much more responsive, has more pep and gets better MPG. 93 wins hands down. I know GM says it will run on 87 and it does but so much better on 93.

 

[Joegonzales22]

My 1.4 loves 93! I averaged 36.3 mpg on my last tank in my auto. I must say, the Cruze continues to impress me.

 

[litesong]

I use whichever one has no ethanol in it......91(octane), 93..... LS 1.8....it runs 1l/100km less (6 MPG better) than regular gas, which around here contains 10% ethanol. We still have my wife's Cruze, a LT 1.4T, and she's been doing the same.

Yes, 100% gasoline works better than 10% ethanol blends. But I never got mpg increases as high as you did!! My 3 previous cars got 8% to 5%(3 to 2mpg) better mpg, but not 6mpg better. My present Hyundai Elantra is getting ~ 3 to 2.5mpg better than ethanol blends.

 

[jalaner]

So, to get the proper performance from the gas Cruze in a hot climate you have to pay diesel prices for premium. Using that math my CTD price premium vs a similar 2LT should be paid for sooner than I thought by higher highway fuel economy. You gasser owners should not be too envious. The biofuel industry is lobbying hard to make less efficient bio-diesel (B20) mandatory just as they did E10.

 

[spacedout]

he biofuel industry is lobbying hard to make less efficient bio-diesel (B20) mandatory just as they did E10.

B20 still has an energy advantage over E10 gas. Besides 10% ethanol fuel runs so much smoother in the cruze than 100% gas & from my testing & has no where near the improvement in MPG as Aburnet85 or Litesong claim. Gas turbo engines love octane AND ETHANOL!!!!

My test:
http://www.cruzetalk.com/forum/34-1-4l-turbo/60041-e0-91-e10-93-a-2.html#post1162809