I Have ran 89 octane in my tl since I got it. I am wondering what the actual manual (not ppls opinion) reccomends, my car did not come with a manual.

Also at macewen they have 89 octane 15 percent ethanol, how does this work?

 

Manual states 91 or above only

 

^ agree.

Wrong forum as well. You should be posting in the 3rd gen forum.

 

premium fuel only...in my 3g tl, i had much better gas miliage with premium vrs 89, so dont do yourself any favors by putting 89 in....

 

This is dumb, but I always thought 89 was premium, just lower grade. Weird...

Are you sure the manual say 91 only?

 

mid grade is 89, premium is 91 or higher...your owners manual states premium grade with a pump octane of 91 or higher...

you can download or view your owners manual online at www.owners.acura.com

 

I had a 2006 and it certainly did say 91 octane.

 

Ok well since I have been running 89 octane for the last year. I have never noticed any differences in the engine noises, or anything at all for that matter. I have used Premium several times too, same deal.

I get 19mpg per 100 Kilometers, which is what our cars should get.

The only difference I notice is that when I fill up with premium my range indicator in the car states 612kms remaining, where on mid grade it states 412. Yet on both types of gas I get 19mpg, and only 400-450 kms...

 

think of 89 octane as McDonalds and 91 octane as home made healthy meals. Both will satisfy the hunger and will fill you up. However, you will suffer all kinds of problems (watch supersize me) as opposed to the healthy food where you will live longer and be more fit.

This is how your car will respond. If you cant afford the 91 octane buy a honda accord.
These engines are high compression engines that require a higher octane rating to prevent detonation and irregular burning in the combustion chamber....

but whatever..... its your car.

 

that is a good point. Sort of...except you didn't really mention what I get with 91 vs 89

 

the opposite of what you get from 89. Your car will just run better. I promise that car manufacturers arent telling you to use 91 for their benefit. Its for your benefit. If they start telling you to use special windshield washer fluid made specifically by them then that is where it benefits the manufacturer.

Its to your benefit to use the recommended fuel..... but its ultimately your choice.

 

Ok well quit talking shit, tell me why it is better, what makes it better and how...and don't google it..let's see what you got to say.Im tired of ppl talkin smack on AZ when they got nothing to really back it with up with...

The stage is yours hommie!

 

No one is talking shit girl scout, calm down. Put whatever the fuck you want in your car. If you want, I will pee in your gas tank for you.... since you don't care what goes in your tank.

I dont need to explain shit. You came here asking questions, your questions were answered. If you dont like it, then dont ask.

Perhaps YOU should GOOGLE it GOOOOOOO Canucks!!!!!

 

Higher ignition temps and compression rates are achieved with 92-93 octane gas. More comp = more hp. Additionally you would get better mileage, as your engine is not retarding that spark sooner in the stroke to avoid detonation under all that heat and pressure. Put some 92+ in the tank, your car will thank you!

P.S. OP is good guy!

 

Im pretty sure it was already answered. If the OP is an OK guy, he needs to calm down and read..... IMO of course

 

Murky,
I was trying to convey that YOU were the good guy!
Marco

 

thanks Marco... OP refers to original poster or originating poster...... BTW I replied to the BBK thread.... Im in.

 

Sweeeet...That explains a few posts I thought were rudely directed at me. Whoops.

 

^lol

 

the bottom line is that the engine is tuned to use 91 octane, not 89...i can guarantee you that you dont get the same gas miliage or performance from the 89 octane vrs the 91....will your car run fine with 89, yes...will it run better and get better miliage with 91 yes...your waisting your money with 89 octane as you will get better miliage with the 91 and it will offset the cost difference of the 89....

 

Two words: Engine Knocking.

 

I wish I could find an article I read a few years back by some consumer advocacy group. Most gas pumps say "minimum octane rating R+M/2 method". There are really only two grades of gasoline - regular, and premium. Mid-grade is a blend of the two. This article claimed the methods used to blend isn't very precise, so they adjust mid grade blend on the high side to make up for it. They are legal as long as the "minimum" octane never drops below 89. This group tested several gas stations' mid grade, and discovered most ran 90 to 91 rather than 89 (depending on whether premium was 93 or 92). Some gas pumps have mechanical "odometer" type displays that count the gallons run through - when running mid grade watch them closely. One corresponds to the 87, the other top grade. I've noticed some run identically while pumping mid grade. On a pump that has 93 as the top grade, that means you are really getting at least 90 octane. If you are at a Sunoco where their top grade is 94, you may actually be getting 90.5 assuming the minimum octane ratings at the top and bottom grades are spot on...

So, if you are a cheap guy like I am, I suggest logging your mileage on several tanks of "89", and several tanks of premium; and try to drive consistently, and use the same gas station. If your mileage stays about the same, your gas station's mid grade may be close enough to 91 that you can save a couple bucks a tank and have no fear you're hurting your car.

In my '07 335i, I wound up going exclusively mid grade. My mileage never dropped. However, my owners manual actually stated 89 would be OK. I decided the premium recommendation BMW was using for that engine was more or less a marketing gimmick (ie "the ultimate driving machine requires the ultimate tier 1 premium gasoline, premium synthetic oil, coolant, etc etc").

So far with my ''10 TL 6MT, I've kept using premium. I ran one tank of mid grade the 1st tank due to my habit with my last car. My mileage increased when I switched to premium. However, it has been increasing ever since - so I may not run my test on the TL until well after my car has a good 10,000 break-in miles.

I'm inclined to believe the 3.7 TL engine definitely needs premium, since they may very well have gotten the bigger displacement by increasing the stroke of the 3.5 without changing the heads all that much. The resulting higher compression ratio would need the premium to prevent early detonation.

I haven't looked to see if there are compression ratio differences between the Accord/Odyssey 3.5 that accepts 87 and TSX/TL 3.5 that requires premium (I may be too ignorant and not realize these aren't all J series Honda engines). They have higher HP ratings, but don't really know if that's due to higher compression or better flow...If the compression ratios are the same, I'd tend to believe the premium requirement for those Acuras are more on the marketing hype side of things...

From an engineering perspective, everything has tolerances. Acura engineers might specify 91, while 89.5 to 90 might be OK in 95% of conditions (ie you'll still get detonation that requires the computer to retard the timing going up a mountain with the A/C on a 95 degree day at 10,000 ft altitude). So, given the tolerance in gas pump blending, the tolerance taken by Acura engine designers, it may come down that running mid grade is OK 85.34259% of the time while running 91 or higher is good 99.999% of the time; and then the consumer must decide whether that ~15% extra margin for the more extreme engine loading conditions is worth an extra couple a bucks a tank.

Given my BMW was burning oil and coolant in the first 15,000 miles, I decided to turn it in at the end of the lease and not worry over whether 89 was doing anything additional to hurt the car's longevity (I suspect a head gasket will go long before a valve or piston will burn through from pre-detonation). With the TL, I bought to own for a long time, so I will likely spend the extra 2 bucks to cover that extra 15%...unless gas gets close to $4/gallon and there's a much bigger than 15 cent spread between the two.

Thanks.

 

I've got to add one more thing to get everyone thinking....

Ethanol is now the most common octane booster (note E85 is something like 110 octane). Given that ethanol costs less per gallon than straight gasoline, it seems it would cost the oil companies more per gallon for 87 octane rated gasoline than 93 or 94. Note the gas pumps say "may contain up to 10% ethanol". It makes me think the premium is what has the 10% while the 87 has less ethanol in it.

OR, it all has 10% ethanol in it since it is the cheapest cost per gallon for the oil companies, and the "minimum" octane rating is well-exceeded at the regular and mid grades.

 

are you saying e85 or e89 is premium, its late and im buzzing so im fonsued

 

i dont believe you can use either one of these fuels in your car....

 

Not another one of these threads, and in the wrong section, too...

 

^^ No kidding... I don't know why people would spend $40k on a car and then put in anything other than what the manual says. To save like $4 at each fill up? Maybe you should have got a civic instead, my wife's get's 35mpg on the highway on regular.

 

...because some people got their 40K by scrimping and saving in the first place. Frugal habits are hard to break, just like the bad habits of those who seem to never have the patience to save their money before they spend it - they pay the credit card companies to control their spending for them (ie run it to max, pay it down, run it to max, pay it down...). Saving $4 here and there on a daily/weekly basis adds up to significant money by the time the year is out.

 

No, e fuels are not labeled as premium unleaded gasoline....e85 is 85% ethanol.

Gasoline rated at 87, 89, and premium (91 thru 94) all may have up to 10% ethanol (or it says that on most of those gas pumps these days). Technically, they could be labeled as E10. Ethanol is an oxygenate that has replaced MTBE, I believe, due to the health hazards of that chemical. Straight ethanol is 113 octane, and therefore, can be used as an octane booster.

So, I'm just saying that premium grade gasoline may actually have more ethanol in it than 87 octane rated gas, if you follow the logic that the more ethanol that you add to gasoline, the higher the octane rating. If that is the case, people who spend more per gallon on premium may actually be buying product that costs less for the oil companies to make.

Since all modern cars are now designed to handle E10, it begs the question of whether or not they could handle E20 or E30.

Regarding off topic-ness...I have a 4g TL, and it's debatable whether using 89 or a higher ethanol blend would create a *problem* that needs *fixing*...therefore, this thread is now back on topic.....

 

Goodman Draph, you tell em!

 

dave- yet again you start another damn thread without searching. Do it again, and you will be banned for two weeks. We are all sick of it.

Oh, and this is the 4G forum.

To the others, if you want to discuss ethanol, feel free to start another thread. Thanks.