Removing Bugs and Tar From Coated Paint Safely

Why act fast

What bug splatter and tar do to a finish

Bug residue is not just ugly. Mazda's owner's manual explains that when insects stick to the paint and decompose, corrosive compounds form that can erode the clear coat and color base coat if they are not removed. Heat speeds that up, and an Upstate summer hood can get far hotter than the air temperature.

Tar works differently. It is a sticky petroleum product thrown up from fresh asphalt, patched roads and construction zones, mostly onto the lower doors, rocker panels and behind the wheels. It bonds tightly, attracts dirt and can stain lighter colors and film if left for long periods.

A ceramic coating helps with both. Its slick, chemically resistant surface gives residue less to grip, so a lot of it rinses or wipes away in a normal wash. But a coating is a thin layer, not a shield. Bugs baked on for weeks can still mark the coating, and the scrubbing people do to remove them causes more damage than the bugs.

Tar

How to remove tar from a coated car

Tar needs a solvent, because water and soap barely touch it. Use a tar remover that says it is safe on clear coat, coatings and, if you have it, film. Apply it to the spot or to a microfiber towel, let it sit long enough to soften the tar (often under a minute or two; follow the label), then lift the tar with a gentle wiping motion. Repeat rather than pressing harder.

Afterward, wash the area with car shampoo. Solvents leave a residue that attracts dust and can affect toppers. Mazda's owner's manual notes that a spot remover used for oil and tar will usually also take off the wax, and recommends rewaxing those areas even if the rest of the car does not need it. On a coated car, the equivalent is a quick coat of topper on the panels you treated.

Work in small areas, on cool panels, and never let solvent dry on the surface. On textured black plastic trim, check that the product is safe for plastics first; some solvents can leave a light haze on uncoated trim.

Do not

Things that do more damage than the bugs

• Scouring pads, the green side of a kitchen sponge or steel wool. They cut through coating and clear coat.
• Dry paper towels or napkins. Paper is abrasive when dry and smears residue.
• Gas station squeegees on paint. They carry grit from every car before yours.
• Fingernails, razor blades or plastic scrapers on paint or film.
• Gasoline, kerosene, lacquer thinner or acetone. Mazda's manual warns against solvents like these on interior surfaces for a reason; on exterior coatings, film and trim they are just as risky.
• Letting any remover dry in the sun, where it can leave its own stain.

Damage check

If marks remain after cleaning

If you have cleaned an area properly and still see the outline of a bug or a dull spot, the residue has likely marked the surface. On a coated car, that mark may be in the coating rather than the paint, which is good news: the coating took the hit. Light marks can often be improved with a gentle hand polish followed by a topper, but anything visible from a few feet away deserves a professional look before you start rubbing.

On film, a stain that does not clean off sometimes fades with heat and time, and sometimes means that section of film needs replacing. The film is doing its job either way: replacing film is simpler than repainting a bumper.