shinyblind

How critical is it if you miss fueling with premium and use the 87 octane instead?

My wife says I'll have to remind her or she'll forget!

Book says NOT to use fuel containing Methanol... should I assume that Ethanol is thte same thing and should not be used?

So... is it more critical if I do use Premium fuel that does contains Methanol... or a lower grade fuel (87 octane) that does Not contain Methanol??

Or is it critical to always ONLY use Premium fuel containing NO Methanol??

Thank you all in advance.

Sal

I'm going to post an oil question next!

mrgold35

It is my understanding Methanol can be more corrosive to plastics and certain metals. I don't think the Acura fuel system was engineered with methanol in mind. You could void your warranty if you use methanol and damage your fuel system or engine. The Acura vehicles are made to run with fuel with up to 10% ethanol with no problems.

http://owners.acura.com/Maintenance/...&id=oxygenated

The RDX is tuned to run with 91 octane; but, you can run a lower octane if the higher stuff is not around. Higher octane numbers of fuel is designed to resist pre-detonation before the spark plug can ignite the fuel. Remember in the good ole’ days when your Dad’s Delta 88 454ci V-8 land yacht would knock or “ping” like crazy. It was the carbon build up in the cylinders retaining heat and igniting the gas before the spark plug did. That “ping” was the ignited fuel hitting against the cylinder head like a hammer robbing you of power and mpgs. Modern performance cars now have high compression engines and/or superchargers/turbos that compress the air/fuel mixture to a very high psi. That high psi fuel/air will heat up when compressed in the cylinder and may cause pre-detonation if you use low octane fuels.

Side Note: Direct injection (DI) engine spray the fuel directly in the cylinders that helps cool down the temps. This is one of the reasons why DI engines can run higher compression and 87 octane fuels (hint-hint Acura).

The RDX is smart enough to listen for knocking/pinging and it will adjust the engine timing to eliminate the problem. Upside no pinging with 87 octain fuel. Downside less HP with the adjustment and you might use more fuel. You may not get all 240 HP and 17/22 mpgs city/hwy when you use 87 octane fuel.

justnspace

iTrader: (1)

^but, it is imparative that you use 91 or better to prevent knock/ping/pre-detonation.

you're right that the computer will pull timing, but that results in a loss of power and FUEL economy.

your motor is turbocharged and I would not put anything less than 91 octane.

Joe Las Vegas

Add a bottle of octane booster to the tank right away, and why does your wife need to be reminded all the time to use 91, it's not rocket science, it's not that hard to remember, unless you have 10+ cars.

windowlickingood

^ octane booster will do diddly squat for a 87 fill. most of the octane boosters barely raise the oct rating a half a point

http://www.youtube.com/watch?v=2jbcC...layer_embedded

you are better off filling it with a couple gallons of race fuel.

justnspace

iTrader: (1)

a mix of toluene will do the same!

Kaze66218

Watching that video made me wish I had a rhd mugen civic rr.

Found a few places on my way to Florida that carried no ethanol fuel, in poor dixie farm towns across the south. That's were I'd go.

Just a suggestion, please don't call pump gas e10~ e15 for any reason, E85 isn't exactly pump either.

I'll correct with another post if im wrong, but, your average pump gas is methanol mix.

Kaze66218

To correct,

MTBE Gasoline uses a methanol mix, but since looking into it methanol is corrosive when paired with aluminum. Also produces water on combustion. I remember europe used this as I stated in why there might be differences in hp for Dif RDX owners.

The likely hood of you finding a significant amount of methyl alcohol in a fill up means that you have flux capacitor-- like me, had to say it crazycated--and you had pit lane fill you up. Otherwords there shouldn't be any methyl pumps conti- US.

Not to create a bunch of schizophrenic panic. But I'd be more worried my pump gas is what I'm paying for in south Florida I paid for 93 and got 89 or worse...

DRR98

Everyone here is free to say and do what they want. Saying is one thing and doing is another. If you do use anything below 91 octane and put a good load to the motor, you have done the first bit of damage to your motor.

When the knock sensor picks up a knock event, it has already happened.

Wait what happened? A knock event = damage