Oldguychuck

I agree and would not run E85 and would not even try for a conversion as I see no advantage. You said mpg was 13 in town and 21.5 on the hwy however that seems very low. Actually I have not see anyone running regular E90 to have mpg that low. Almost too low for the E85 fuel alone and would expect something else is going on perhaps related to the E85 effecting your engine. Perhaps the E85 was not the great advantage you thought it was. I would bow to the wisdom on this board and NOT mess with E85 in the Corvette.

djyankees31

I'm sure he's using E85 for the performance benefits and not for mileage. The higher octane and cooling benefits in the combustion chamber allow for higher degrees of timing thus better performance.

speedlink

It's actually the opposite. E90 having less ethanol would actually have a very slight MPG increase. Getting zero ethanol in your gas would be even better mileage.

mschuyler

E85 means 85% ethanol and 15% gasoline
E90 means 90% ethanol and 10% gasoline

https://en.wikipedia.org/wiki/E85



Any questions?

Oldguychuck

I run non ethanol fuel in most of my vehicles. Luckily we have numerous stations that sell non ethanol.
I understand some of the reasons why someone would want to run E85 in some engines as djyankees stated but I would not do it in the Vette. Before I would go the E85 route for more power, I would do forced induction or nitrous instead but that is just me...
However, to answer the OP would do as mentioned previously and drain the tank if you suspect bad fuel and go from there..

Oldguychuck

Mschuyler, thanks for correcting me. Got turned around and confused E90 with regular fuel with only 10% ethanol. There is a huge difference between a fuel that has 10% ethanol like most of us use and a fuel that has 85% ethanol...The vette is designed run on no more than 10% ethanol .

mschuyler

I didn't. I was responding to speedlink. I see no good reason to run E85 unless you are tracking the car. And if OP is doing despite what GM says, he's running a warranty risk. Plus his mileage is much wore than average.

Gary barnes 1098

The op surely must have got some bad e85. Numerous speed shops and very very good ones swear by the benifets of e85, And convert c7 Vettes over every day!! They all will tell you that when they open up an engine it’s obvious when the cars using e85,motor internals are sooo much cleaner. The people knocking this fuel obviously don’t know the real facts about it and our c7’s. This car can safely run this fuel and benefits greatly with the proper tune!!! Then again maybe I’m wrong.....these pro engine builders here saying it’s junk know more than Ecs,katech,pray performance,lmr and other numerous big builders??? Gimme a break!!!! **** like this irritates the hell out of me!!!

RichieRichZ06

It's more than likely an injector starting to fail. As other mentioned, contaminated or bad fuel would not just effect one cylinder. Most good tuners will only tune for E50 or E60 so even a batch of fuel with low ethanol content should still run fine, especially on an otherwise stock car.

There is some junk E85 out there so I recommend testing it before just dumping it in the car, but I don't think the OP's issue had anything to do with fuel.

Matthewstorm

My performance shop, whom I do trust, as they have never steered me wrong, so there's no disadvantages to running a converted and properly tuned Corvette on E85. It does provide significantly more power. I'm just a little about this occurring only once. Now my concern is this could happen somewhere far from home. I am awaiting the arrival of a fuel testing kit and I'll be testing the pump that I last used. It's just strange this happened only once.

PatternDayTrader

Its not that strange that it happened only once, A coil or spark plug problem would start out by malfunctioning infrequently, and would get worse over time.
Obviously, if its bad fuel then it would be strange it happened only once.