Goo-gone may work on your coke....but I've got something that will blow its socks off....Prep-Sol. Its flammable, so be forewarned. It is clear and flows like water....one whiff will tell you its not, though.
But this stuff is used to prep surfaces for paint. So it'll evaporate. Don't go to AutoZone or Pepboys....for as far as I know, they don't carry it. duPont puts it out...so swing by your local mini chain of slightly more expensive auto stores and they should have it. In fact, swing by an automotive store that has a dedicated paint dept...they'll have it.
It took off that rear tail light adhesive sealant tar when I swapped out my corners for JDM lights; it takes pine tree sap/pitch off your car's finish without harming your clear coat (I've done it), it'll get road grime (oil, tar, bubble gum) off your rocker panels and out of the inside of your wheels....
so yes, it'll totally rid your car of that measly mess you call coke.
Its very easy to use. Fold up a paper towel and tightly place it over the opening of the container (1 gallon, metal), tip container onto papertowel and back quickly to get liquid onto PT, rub affected area (lightly on paint, harder on non-painted surfaces) and repeat till mess is gone. Keep a clean dry piece of PT handy to wipe away excess Prep-Sol....you shouldn't let a puddle of it just sit there it evaporate....but a thin film of it is okay.
Keep flipping the folds of the PT to get a clean surface so as to not work in the grim you just took off....and it WILL come off!!
I've used it for oil, grease, bird poo, pine tree pitch, bug guts, road grime, brake dust on wheels, and for actual paint prep.
Stuff is great. I haven't come across a mess I couldn't handle with it.
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