Have the fuel filters been replaced annually? That might be a suspect since it was running fine in the upper RMPs. BTW TxBill, the same thing happened on our 240d with the fuel gauge (on a very cold morning out on the interstate). Since that happened, I always keep 2 gallons of #2 in the trunk .... 1 gallon to prime the pump, 1 gallon to find a service station
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