Removing duct tape residue from the exterior of your car can seem challenging because duct tape has glue that can be very resistant to cleaning. It might have been part of a temporary repair to a window, but once that is replaced, the last thing anyone wants is that remaining gummy residue that attracts all manner of dirt and dust to the body of your car. Since the sticky glue is on the metal surface of your car, extra caution and different tools are needed in order to avoid scraping or scratching your car's paint. Razor blades or plastic scrapers should never be used on the car's exterior because this will definitely result in unsightly scratches. Here are a few options to help you clean up the duct tape residue on your metal car paint finish.
Step 1 - Soak the Glue
Hold a wet wash rag over the glue for several minutes. This should loosen it to some extent where it can at least be partially wiped off. Soap is not necessary at this point and may actually add more to the residue to be cleaned off and prolong the chore. The longer the duct tape was actually on your car, the more difficult the glue will be to completely remove, so some patience will probably be required with this step. Use some pressure and wipe off as much of the duct tape residue as possible at this point.
Step 2 - Use the Solvent
Choose a commercial solvent that is intended for auto body spot cleaning. These are available at any auto supply store or auto department. Apply with a clean, soft cloth; a piece of old T-shirt works perfectly. If in doubt, check with the retailer to be sure the solvent is intended to degrease with no effect on your car's paint job. If you can, test the solvent on a small hidden area of your car's paint before purchasing. These chemically break down the bonds between the residue and the metal surface. Do not ever use nail polish remover or acetone to try to remove the duct tape glue since these can remove the top layer of paint, resulting in unsightly spots and potentially expensive paint matching and repair. Also do not use WD-40 which can cause an oily residue to soak into your car's paint, and this is even more difficult to completely clean off than the original duct tape residue.
Step 3 - Remove any Traces
Use the edge of an expired credit or debit card or exhausted gift card to carefully scrape off any remaining duct tape residue. These have been found to be less abrasive to your car's paint; they are thicker than the plastic scrapers that are normally used to remove bumper sticker residue from chrome or glass surfaces of your vehicle. Once you have removed the last remaining duct tape glue, be sure to cut up the old cards before throwing them away. If necessary, reapply a final coat of degreaser and follow any instructions that come with it to remove any last bits. The next time you wash and dry your car as normal, there should be no visible or tactile trace of the duct tape residue.