Gasoline guru help - Ethanol 10%

[scottyb]

I noticed new LARGE stickers at the pump yesterday:
"Fuel contains less than 10% Ethanol"
I filled up with 93.
Now the car doesn't like boost levels above 15lbs - breaks up, when I normally can creep up on 18lbs without alky. Now I may be too quick to judge since there was a drastic ambient temerature change as well, but I don't ever recall issues such as this with cooler weather. In fact, the car usually runs much smoother in cold weather.

First question: Was there a level of ethanol before the "sticker" was applied - ie always has been ethanol in gasoline? I thought there was.

Second: If there is a different concentration of ethanol now, do you think it could be to blame? My thought was 'no', especially if i'm not running lean.

 

[TurboDave]

They've started that around here just recently also!

Been going on out in Kalifornia for years. They call it "oxygenated" gas (winter blend). Always had to reduce the boost a pound or two when they did it.

Instead of running 11.8:1 to 12:1, I've had to turn the A/F ration up to 11.5:1 to compensate.

 

[scottyb]

A day later and now thar car can't make 5lbs without popping. I know it sounds like a non-fuel-related problem, but I'm going to burn off this tank and fill with another brand before I start troubleshooting other parts.

 

[mygn276]

Sounds like you have more the 10% ethanol in your tank. Try richening your fuel presure up more. Ethonal is a great fuel, the problem is you have to run more of it to keep from leaning out.