This may sound like a very stupid question but I still want to know 100%...

Does it make ANY difference on a 06-07 LS/LT (2.2L) Cobalt as for the type of gas you put in? (87, 89 91 or even 94)

I'm figuring that even if it did a small difference, I'd pay the difference but if really, there is NOTHING more for those engine, I could save money...

Thanks in advance for answering this maybe stupid question!

 

use 87 thats what the 2.2l is set up for. it will give you absolutely no gains using higher octane fuel

 

Use regular just like the users manual says...its what the car is tuned for...anything else is a waste of money.

 

That was exactly the answer I was loooking for; thanks a lot guys!

 

Im not positive about this, but I was told using anything higher the REG. would do more harm then it would good, because the resistance to combustion, is greater with higher octane. Also I think it works backwards also if you have SS/SC you wouln't want to use lower octane because the combustion level is lower and would ignite prematurely, and would start causing engine knock. If I'm wrong let me know.

 

^Yeah, that's what I've been reading on here. I wasn't aware of it before, but apparently it hurts our cars.

 

87... but some gas stations around here don't have it.. so in a pinch 89 is safe to use in a 2.2L ecotec.

 

the only good that can come from higher octane gass is it will clean out ur valves because it burns little hotter and little cleaner and you should only run it once in a while not everyday... or alot all all.. to much is no good...


like i got some bad fuel form a gas station and my car bogged like crazy so to help burn the bad batch of gas though my tank better i used about a gallon of race fuel just to pep up the mix..." mind you i had 11 gallons of gas in my tank" i wouldn't recommend what i did though

 

you are right, but the reason for it (at least i think so) is the gap on the spark plugs. i think if you guys changed your plugs out you could then use premium. (do some research, or ask someone like Ljavy17) do not take my words as the bible or anything.

 

I run 87 on mine almost 24/7.

Track days I mix in 89. I haven't noticed a difference running 91 or 93...just gas mileage is a lot less because it burns faster. I'm running rich as hell...so it doesn't give me any good performance running higher so I stick with 87 with a fuel treatment every now and then.

If you are worried about your car being sluggish...do a three stage carbon treatment. Their pricey(for us we charge $190), but well worth it. BUT...have someone who knows how to do the treatment do it...one mistake with this stuff will kill your engine...meaning you have to fork out money for the new engine. I did my three stage at 30K and noticed a difference because the carbon was cleaned out...not from switching gas.

 

higher octane actually makes it run worse on a 2.2 testet it out on my hhr. The engine feels alot better and smoother with 87

 

higher octane does not clean the engine.

 

lets see it burns hotterand it burns cleaner... do i need to take photo evidence of my buddies gsxr tail pipe to prove this... because we had an arguement about it last summer and i proved to be right.. we burned a tank of 110 though his gsxr

A: he go more pep out of the bike
B: his exaust pipe went from black to clean like that....
C: ther is no ethonal witch isnt good for the engine in the firstplace
i think i can find a photo to prove it... if u want

 

the higher the octane the more stable the fuel octane rating refers the detonation resistance of fuel

 

you can use any fuel

But, its tuned for 87. If you read other posts, I have read several times about getting less mpg using high test in the 2.2.

So if you use high test,
1. you pay more
2. you get less mpg
3. you fill up again sooner and pay more

100% correct

 

i changed to the high 94 octane and did 3 full tanks and i realized i was just wasting money and went back to regular and noticed NO difference...except my bank account kept money in it instead of being empty

 

i use 87 but maybe once a month i stick a tank of shell plus or w/e its called. cleans out the car and is rated #1 in the country for that type of gas.

 

i run premium, but thats because im on the bottle!

 

I've been runnin 89 for a month or so in my 2.2 and I noticed a little more smoothness in takeoffs and idle when runnin 89 vs 87. I'm pretty sure it doesn't harm the car if you run higher than recc octane... I've ran 89 for 2000+ miles no probs

 

exactly. if the car is suppose to run on 87, use it. unless of course you are boosted, high comp, or running da nawz. usually the car will get worse gas mileage because it is unable to properly burn the mixture.

 

I have an LS and I use 87. I switched over to 93 and didn't see a difference other than the price. I'm sticking with the 87.

 

I talked to Trifecta and the Cobalt 2.2 has two programs, one for low and one for high octane. If you run high octane, the motor detects it and compensates. This might ruin an older car without such technology that requires 87, but not on the Cobalt.

The 2.2 is already pushing it by having a 10.1:1 compression ratio and running 87 octane.
It is borderline running lean, and higher octane prevents pinging. Not saying with a stock 2.2 you need high octane, but for the max bolt on guys, it might be better.

Getting a CEL telling you your running lean is bad.
With higher octane, you will still not have enough fuel to air, but it is more resistant to pinging which is what can happen. When it does, it scores the pistons and can damage the valves.

I just put in a tank of 91 octane and the car runs a lot better than with 87.
I don't have to press down on the gas as much to get the same result.

 

^It's in your mind about the 91 being better ("I don't have to press down on the gas as much to get the same result.") unless you're tuned.

Also, you brought up a thread from OVER 2 years ago.

 

Going with a higher octane can help if you are tuned for it, your ECU can pull timing for a lower octane. Higher octane though the ECU has trouble dealing with timing correctly. Also a higher octane can cause your exhaust temps to be higher and possibly melt your cat....mine is partally melted

 

Its called I actually did the search and this touched base on the subject I was seeking.
No one likes it when you start a new thread and always yells "search", can't win.