Don't try this! We mean it. DO NOT TRY THIS! The American Coalition for Ethanol ran a 2000 Chevy Tahoe, not a flex-fuel vehicle, exclusively on E85 for 100,000 miles. Then they stripped down the engine and took a look. Everything looked fine. Fuel lines, fuel pumps, etc. In fact, they say a few things looked better than normal. The video includes a look at the parts of the engine from that Tahoe.
Again, DO NOT TRY THIS but car companies know they must comply with small percentage blends of ethanol. So most cars made since the early '90s can handle ethanol. The only problem is that non flex-fuel vehicles don't have the sensors necessary to detect ethanol content. They also don't have the control software to manage the air fuel mixture properly. So your car might run on E85, it just won't run well. It could also cause major damage and using E85 usually voids your warranty. So that's why you should not try it.
This leads to an interesting potential. What if a private or public group went to car manufacturers or did tests on their own to find out which cars could withstand E85? Then this was made available to the public. This would be great for the ethanol market. Many people think ethanol is bad because it's more polluting and less efficient. The creation of a mild or soft flex fuel standard won't make them happy.
(fellow AutoblogGreen blogger Sam Abuelsamid contributed to this article)