Why are there water marks after washing the car myself?
2 Answers
Water marks after washing the car may indicate that the vehicle was not cleaned thoroughly, and a re-wash should resolve the issue. There are generally three areas where water should not be sprayed during car washing, as detailed below: 1. Engine compartment: Many vehicles do not meet the IP67 waterproof standard, so water should not be directly sprayed into the engine compartment, as this could damage the engine and related components. 2. Electrical component connectors: These connectors are usually well-hidden, so extra care should be taken during washing to avoid water ingress, which could cause short circuits and damage parts of the car's electrical system. 3. Exhaust pipe: If water enters the exhaust pipe, it can flow back into the internal parts, potentially damaging the filter and leading to increased carbon buildup over time.
I've also encountered water spots when washing my car myself. Looking back, the main reason was too many minerals in the water, especially since the tap water in our neighborhood has high hard water content. After washing, when the water evaporates, it leaves white or gray spots on the car, which look really annoying. Another reason was that sometimes I was in a hurry and didn't rinse off the soap suds thoroughly, leaving detergent residue that would stick to the paint and form marks after drying. Weather factors also play a role—if you wash the car under strong sunlight, the water dries too quickly, and the residue doesn't have time to disperse. Based on experience, I now use filtered water or bottled purified water to reduce mineral content when washing, and I immediately dry the surface with a microfiber cloth afterward to avoid most water spots. This method is simple and cost-effective, and my old car hasn't had any spots for half a year.
