Here in MN, the powers that be have seen fit to give the farmers a boost by requiring that nearly all gasoline sold contain 10% oxygenated fuel (gasohol made from corn). Some dealers sell non-oxygenated fuel but it is posted to be used only in antique or collector cars, boat motors, or snomobiles.
I've heard very mixed messages on using this stuff. The non-oxygenated fuel sold is unleaded, but the pump at the station I buy it from has a larger dispenser nozzle that does not fit in the smaller fuel filler hole on unleaded cars. I've made an adaptor to fit the nozzle on one end and my car on the other.
Any opinions as to the use of oxygenated fuel in MB cars? Mine is a 1991 420SEL.