engine died at 65 mph
 

Hi, have 1991 500SL. this problem has been on and off for a number of years. have had various parts replaced at MB dealer. anyone have any ideas what they would look at first. use to die in nieghborhood, this was first time on expressway at this speed in left lane. thought it was my day to die! Help. would like to swagger into shop with some knowledge of whats what. thanks in advance, wendy