yes if you were to do this the only thing i would do is dont drive the car while the diesel is still in the tank, drain all the fuel out of the tank and pray that it didnt screw something up. i suggest you dont do this unless its an actual diesel beamer
Actually diesel is ok to have in the system. It actually can help most of your fuel injector cleaners now days are nothing more then diesel fuel with adatives. So a gallon of diesel fuel diluded with 17 gallons of premium fuel so nothing could be hurt out of this.
check out this forum I posted your question on the e60 forum. http://forums.e60.net/index.php?showtopic=59225
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