I'm back to 94 Regular unleaded and the car feels great. Also my pocket feels better too. The 98 gave me a feeling of pressure to go at lights under gear. We don't normally free the auto gears at lights. Its not so comfortable to do it in a Benz due to the noise of the gear change and the slight jerk. In my Camry, you hear and feel nothing when you shift to free at the lights. Thats why I always do this in my Camry esp when trains are going left and right, sometimes there are 4 trains and it releases your tensions at the wheel(usually need to pull the parking brake lever too). I may have the idle speed reduced to a lower rate like 600 or 650 if it doesn't result in the engine stalling. Now its more like 900 or 850. What is the recommended level???