Hello Everyone,new guy here.I'm been having a problem lately.I have a 1996 E320.Great Car,but,lately I've been having a problem with engine misfire.Changed the plugs,replaced with Bosch Platinum 2 plugs.Misfire got worse.Replaced ignition coils,no change.Replaced plugs again with standard Platinum plugs.Problem cleared up for a short time,but is back again.Happens at idle,transmission in gear.Code reader says trouble code 300 and 302,multiple misfire.I live in New Mexico(Elevation 5290 ft. I'm a very capable auto mechanic,and have been for over 30 years.Have owned 6 mercedes before and have never had a problem outlast me,but this one has me stumped.Any Help or suggestions you have would be very appreciated.Thanks again,and you have a great forum..