After a puncture: plug, patch, or replace?
A puncture rarely announces itself. When you do find one, the next decision is whether the tire can be saved. Here is how tire professionals generally think about it.
Where the hole is decides most of it
Punctures in the central tread are the ones a shop can usually repair. Damage in the shoulder or the sidewall generally cannot be repaired, because those areas flex too much for a repair to hold. That tire needs replacing.
A plug on its own is a roadside fix
A plug pushed in from the outside can get you moving again, but tire professionals generally treat it as temporary. A proper repair is made from the inside, with the tire off the wheel, so the inner surface can be checked as well as sealed.
The easiest puncture to deal with is the one that sealed before you knew about it.
Driving on it changes the answer
A tire driven while badly underinflated can be damaged inside even when the outside looks fine. That hidden damage is why a shop wants the tire off the wheel before deciding, and why a tire that ran flat is often replaced rather than repaired.
When replacement is the answer
Sidewall or shoulder damage, a cut or a bulge, damage from running flat, tread close to the wear bars, or repairs too close to one another. In any of these cases, replacing the tire is the safe choice.
Where Nano Polymer fits
Nano Polymer is not a repair for a tire that is already damaged. It works the other way round. On a treated tire, a tread puncture is sealed the moment it is made, so pressure holds and the hole never becomes the slow leak that leads to the decisions above.
In short
If a tire is already damaged, have a tire professional inspect it first. For the healthy tires on your vehicle, find out whether a certified applicator covers your area.
Start where the funnel starts.
Coverage first, so you see the real answer for your area before anything else.
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