Why is the paint peeling off my bumper?
Also calledAdhesion Loss Plastic Parts, Poor adhesion on plastic parts
Bumpers peeling while the metal panels stay perfect is a known fault. It is not the sun and not your fault. Paint on plastic needs the plastic cleaned of mould release agent and an adhesion primer first. Skipping these steps is what causes it. The metal being fine is the proof, because both got the same weather.
What kind of repair does it need?
Stripping the bumper, cleaning and sanding the plastic properly, then adhesion promoter and flexible primer, then colour and clear. It all has to come off. New paint over paint that is letting go fails the same way.
Adhesion promoter and flexible primer are the steps that were missed the first time. New paint over paint that is already letting go fails the same way, faster.
What to do next
Find out if the car has been in a crash. Peeling only on plastic is often an old repair, and then it is a workmanship fault for whoever did it. A panel shop can usually tell if a bumper has been painted before. If it is factory paint, compare the price of a new painted bumper with the price to refinish yours.
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