What Causes a Tire Leak When the Leak Point Cannot Be Found?
2 Answers
Tire leaks where the leak point cannot be found may be due to the following reasons: Hidden Location: If a tire is punctured by a foreign object, it can usually be found by carefully inspecting the tire surface. If the puncture is in a hidden location, you can sprinkle water on the tire surface to locate bubbles or even hear a hissing sound. Pay Attention to the Sidewall: As tire rubber ages, deep grooves may appear on the sidewall. However, as long as the sidewall has not been impacted and the cords are intact, the tire can still be used. The triangular indicator on the sidewall helps locate a raised mark in the tread grooves, which determines the actual wear limit of the tire. That value should be greater than 1.6 millimeters.
I've been repairing cars for over a decade and often encounter car owners complaining about slow tire leaks with no visible puncture points. Actually, the most common causes are aging valve cores or oxidation/rust on the wheel rim edges leading to slow air loss. Wheel rim deformation is the most easily overlooked issue - especially with alloy wheels after scraping against curbs - where the damage isn't visible to the naked eye but affects air tightness. There's also a special case where the tire's inner wall gets scratched by disassembly tools, making the damage impossible to detect externally. My suggestion is to remove the tire and perform a water immersion test - this traditional method works best. If that doesn't work, professional air tightness testing equipment must be used. Never delay repairs, as this becomes especially dangerous when driving on highways.
