None at all. Just give it a good soak and wash out with household cleaning products if there's any crap in it, otherwise just drain and refill. Martin #1458 #4426 "Charlie " wrote: > For a DMC which has sat for one year or less, if the fuel is > sitting in that car of course u have to change the gas but what kind > of damage could be done to the tank itself from fuel sitting in > there?? Esp since its plastic?