ok, well i did a little drawing, for anyone who has some experience with chemicals, they will probably understand the major difference just from the drawing. and if not, i hope you just take my word for it... acetone is a MUCH more polar solvent than fuel injector cleaner (see pic's!). a highly polar solvent is not good for all the plastic/rubber on the car.
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then pour some on different types of rubber and plastics and see what happens....