The owners manual says you can use 87 octane but will experience a noticable loss in performance if I recall. I always use 94 octane. On a engine for which premium is recommended the number of degrees of timing advance will be influenced by the fuel you burn.

 

you need to do a little research before you post.
you tell people to read the manual....and obviously you havent.

87 is NOT fine in a 2.4
Unless you enjoy spark knock....and reduced HP......and eventually ruining your engine....

 

93 since day one, but I have run a tank of 91 just to try it.

 

I am sorry but I think this is a bit sensationalist. The 2.4L is not some crazy italian engine that requires only the best fuel or just explodes.

Is there a possibility using 87-90 Octane fuel could reduce power or cause slight knock? Yes. Will it cause the engine to FAIL? Probably not - if it would, I'm sure it would likely say in the owner's manual to only use premium fuel, just as it says on many premium automobiles.

I encourage you to look around at other boards for other vehicles that use the LE5 as therer are many discussions, with testimonies, of folks who only use regular and have encountered no problem. Also - do you honestly think that everyone who has ever owned an LE5 filled up with premium every time.. or at all? What about all those bare-bones Pontiac G6's used by rental car companies.. think they get premium? Do you see those lining the sides of the road?

Of course - with all that said, I pesonally DO use Premium or even Ultra fuels - every time - but I thnk to scare someone into believing if they don't they will cause permanent damage to the engine is just goofy.

 

It Does Say It In The Manual......

like i said. dont tell people to read the manual when you obviously havent yourself.

 

Hey, yeah - I re-read the manual after work and.. I'll conceit.

Though I'm at least half intimidated solely by your darth vader hood.. which is that by the way? Rk Sport?

 

Invader 2. made by VIS racing.

no harm no foul

 

the manual recommends 91 premium for 2.4 and 2.0 engines

my car seems to run much more smooth and accelerate faster (it says if you use lower grades you will see lower acceleration) with premium

use premium, its only 1-2 more dollars in the end, big deal

 

Yeah.. did the math actually on my drive home from work. If you average 20,000 miles a year at 29 mpg, it works out to about $137 a year - which is like $0.37 a day... that's cheaper than you can save starving children for.

 

lol

 

gees i spent 138$ in like a montha nd a half on the balt gees those figures suck. and i only got 5k miles but i dont drive in winter.

ryan.

 

when i bought my 2.4 i asked what they filled it up with....regular....i yelled at them and drove off. Engine was knocking while cruising at low speeds, so i filled it up with 93 for its second tank and have since. no more knock.

 

they should know better. what kinda dealer is that gees. tell them you want a refund on that gas lol.

ryan.

 

My manual says I can use 87. I don't, but if you choose to you can.
Dennis

Document ID# 1571003
2006 Chevrolet Cobalt
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Gasoline Octane
If your vehicle has the 2.2L L4 engine (VIN Code F), use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, you may notice an audible knocking noise when you drive, commonly referred to as spark knock. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If you are using gasoline rated at 87 octane or higher and you hear heavy knocking, your engine needs service.

If your vehicle has the 2.4L L4 engine (VIN Code B) or the 2.0L Supercharged engine (VIN Code P), use premium unleaded gasoline with a posted octane rating of 91 or higher. You may also use regular unleaded gasoline rated at 87 octane or higher, but your vehicle's acceleration may be slightly reduced, and you may notice a slight audible knocking noise, commonly referred to as spark knock. If the octane is less than 87, you may notice a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine. If you are using gasoline rated at 87 octane or higher and you hear heavy knocking, your engine needs service.

 

yeah, even gas of the same octane rating from two different gas stations can make a difference. You can honestly feel the difference in my car from when it has Sheetz 93 and then the Shell V-Power 93. The car obviously runs much better w/ the Shell 93. I try not to get Sheetz gas that often, but I do it sometimes simply b/c at Sheetz you can get everything you need........the new sport compact mags, all kinds of food/drinks AND gas........which equates to less swipes of the debit card and an easier checkbook to manage, lol.