I have been running 91 octane 100% gasoline in my car since I bought it. Has anyone ran the 10% ethanol blend in your car? If so, does it run ok? Pure 100% gasoline is getting harder and harder to find in my area due to the gas prices rising. The gas stations that I used to get 100% gasoline at are now switching to the 10% ethanol blend.

 

That's pretty much all I can buy and it runs great! I think some of the cars will run up to 15% ethanol, not sure about ours.

 

Most cars sold in the US if not all are designed to handle up to 15% ethanol. You should be fine with whatever your average gas station sells.

disclaimer - I am not an IS 500 owner but E10-E15 gas is nothing new and is no problem for any modern vehicle.