
Car paint bubbling is primarily caused by the relatively poor sealing capability of the intermediate coating. Even if there is moisture in the primer and intermediate coating layers, it can evaporate through the micropores of the paint film. However, the topcoat layer has stronger sealing properties, especially with two-component paints that fully cure. If moisture is trapped within the paint film, it cannot escape. Due to fluctuations in weather temperature and the expansion of underlying moisture, localized pressure builds up in the topcoat, leading to bubbling. The reasons for car paint bubbling include: 1. Poor paint quality: This often occurs in low-cost roadside shops that use inferior-quality paints to offer cheap services. 2. Substandard construction conditions and processes: Paint application requires strict conditions and high technical standards. The surface must be completely free of moisture before painting; the initial filling (putty) must be thoroughly dried in a controlled environment before entering the paint booth; the air hoses connected to the spray gun must remain dry, with no moisture allowed. 3. Excessive paint thickness: Carelessness during application or limited technician skills can lead to overly thick paint layers that sag. Additionally, improper polishing afterward can set the stage for future bubbling.

As a veteran driver with twenty years of experience, I've seen many cases of car paint bubbling. The original factory paint is usually of good quality under normal conditions, but over time or due to external factors, bubbling can occur. For example, my own car was parked under a tree in the neighborhood, where accumulated leaves and dirt combined with rainwater seepage caused bubbles to form beneath the paint layer. At first, they were small dots, but later they expanded to the size of a fingernail and felt soft to the touch. A check at the repair shop revealed that rust underneath was the cause. Environment plays a crucial role—coastal areas with high salt spray or industrial pollution zones, where corrosive gases are more prevalent, make paint more prone to bubbling. For prevention, I regularly wash the car body, avoid parking spots with heavy bird droppings or tree sap, and apply a protective wax coating every quarter. Maintenance should start when the car is new, and any bubbling should be addressed promptly to prevent rust from penetrating the metal, which would then incur much higher costs.

With ten years of experience working in an auto repair shop, I've handled numerous cases of paint bubbling. The causes of bubbling in original car paint vary: during the application stage, the base layer wasn't properly cleaned, leaving behind moisture or stains; scratches from daily use allowing water to seep in; or paint film peeling in high-humidity environments. I once repaired a customer's original-paint car and found that the base layer oxides weren't properly removed, requiring complete sanding and repainting after bubbling occurred. Prevention is key—for new cars arriving at the shop, we advise customers to regularly clean hard-to-reach areas, avoid parking in damp spots for extended periods, and apply rust inhibitors to edges. If bubbling has already occurred, don't scratch it randomly; seek a professional shop to test coating thickness and base layer condition, as improper handling may worsen the damage. Regular maintenance like waxing and coating can effectively extend paint life and reduce bubbling risks.

I just got my driver's license and was particularly worried about the original car paint bubbling when buying my first car. After asking several experienced car owners, they all said it could happen. For example, a friend's car was parked outdoors for a long time, rainwater accumulated in the grooves, and later small bubbles appeared on the door panel, costing money to repair. After researching online, I learned that bubbling is usually caused by contamination seeping in or high humidity. Although the original paint is good, it has vulnerable points that need protection. Now I make it a habit to rinse the car weekly, promptly remove bird droppings and tree sap, and park in underground garages to avoid direct sunlight. Prevention is better than cure, and if bubbles are spotted, professional treatment should be sought immediately to prevent spreading.

After retiring, I've driven several cars, and my experience tells me that factory-applied paint under high-quality control is less prone to bubbling. However, environmental changes like increased acid rain or parking by the roadside where oil stains accumulate can lead to small bubbles over time. In my younger days, I used older model cars with thick, durable paint. Nowadays, with heavier air pollution, paint layers have become thinner and require more maintenance. I recommend parking in dry, shaded areas to prevent water from pooling in body crevices and regularly wiping and waxing for protection. If bubbles do appear, don't delay—address them early to prevent rust, and seek a reputable shop for repairs to restore the paint to like-new condition.

As an automotive modification enthusiast, I pay close attention to car paint protection technologies. Modern OEM paint materials offer strong corrosion resistance, but are prone to bubbling under extreme conditions such as coastal salt exposure or chemical pollution zones. When repainting my beloved car, I learned that improper base layer treatment is the most common cause. In daily use, I take care to avoid scratches from hard objects and apply professional coating agents after cleaning. When purchasing a car, I always check the integrity of the original paint. The key to preventing bubbling lies in regular professional evaluations and using moisture-resistant spray treatments.


