gloss3

I just filled up with the ethanol free gas yesterday on my 06 corvette for the first time. Now it won't run or start. Only ran it about 15 minutes. The REDUCED POWER light came on. I am running a Magnason supercharger. I need some help please. Do I need to pump out the gas and go back to the 93 octane I was using?

klwehunt

Was it not ethanol free 93 octane? That's all I run in my SC 08.If it was EF regular could be a problem.

Dano523

Yep, glitch your going to find with ethanol free gas, is that it is a much lower octane rating.

Hence ethanol will bump the octane rating when added to lower octane fuel, so most of the supplies that are offering both fuels, in the case of the ethanol free gas, it has a octane rating of only 83~87. Hence its the same base fuel as the ethanol fuel, before ethanol was added to it to bump it octane rating and make it burn cleaner.

As for with running a super charger, your looking for fuel with at least a 91 octane rating, if you can find fuel with a higher octane rating, the better.
So the problem is not that the fuel is ethanol free, but it has too low of an octane rating instead.

And just a FYI, but the reason that ethanol free gas is offered (over ethanol fuels that burn cleaner) in areas, is that on some lawn and off road type equipment, the ethanol in the fuel cause problem with the fuel lines and carb diaphragms on these devices. So the lower octane fuel is fine to run in them, over running the higher octane fuels with ethanol that will cause problems with them instead.

So in my area, the highest ethanol free gas octane gas your going to find is only 85 octane, since its the same base fuel at the ethanol added fuel, which the ethanol added to that fuel bumps the octane rating up, and make the fuel burn cleaner at the same time. If you can find ethanol free gas with a octane rating of 91 or higher, then should be fine to run.

On the other hand, if all you can find is lower octane ethanol free gas, 91 octane fuel is the highest octane fuel in your area, I would say go the other way, hence add in a Flex fuel sensor, have the car re-tuned to use the sensor and run E85 instead.
With E85, is has a much higher octane rating, and since your burning 30% more fuel (fuel is cooling), going to run cooler as well.

LDB

Gas with ethanol is not made by adding ethanol to standard gas. The problem is that ethanol has a very high vapor pressure, so if you added ethanol to standard gas, you’d be grossly high on vapor pressure. All gas with ethanol is made by shipping a material called BOB (blendstock for oxygenate blending) from the refineries. Its two main characteristics are that it is much lower vapor pressure than standard gas, and it is a few octane lower. That way, when ethanol is added at the distribution terminal, the finished gas with ethanol is on spec. Thus, it’s highly unlikely that the OP’s problem is cause by octane. The most likely explanation is that he got a contaminated batch of gas. That is one of the risks of using ethanol free gas. Since relatively little of it is sold, there’s a greater likelihood that it will be from some fly by night source and thus badly off spec.

I suppose I should admit there’s one way for your theory to be correct, but it would take a seriously unethical gas station owner, and the resulting gas would run so badly that I can’t imagine he’d stay in business for more than a few weeks before being closed down and probably jailed. If he did try to sell a BOB from the above paragraph without adding the ethanol, indeed the gas would be horrid. Its vapor pressure would be so low the car probably wouldn’t start, and its octane would also be low. But that’s a highly unlikely scenario. You can’t make ethanol gas and ethanol free gas from the same base stock by simply adding or not adding the ethanol. Neither the octane nor the vapor pressure would come out right.

SladeX

Confirm the octane rating of the gas station on pure-gas.org if it is correct or not. When traveling through different states, I tend to map out routes that bring me to minimum 91 octane ethanol free gas.

mikeCsix

In my area, I have been able to find ethanol free premium fuel at about 91 octane and have run it without issue - unless you call 10% mileage increase an issue. The caveat is it wasn't top tier fuel. OTOH, the cars were made to run on ethanol free fuel so that shouldn't be the issue. More likely contaminated fuel as seen on the forum from time to time. You might disconnect the fuel line and run the fuel pump to pump some gasoline into a clear container to see what you are working with.

NY09C6

91 octane non ethanol is also available by me.

This likely various by region though. In most elevated areas the octane ratings available are usually lower.