Why does my tire keep losing air?
The short answer
A tire that needs air every week has a slow leak — most often a nail or screw in the tread, a corroded wheel bead seat, or a leaking valve stem. Most tread punctures are repairable for about $35. Driving on chronic underinflation overheats the tire and can total it.
Reviewed by Joe Zeiter
Service Director · Grote service team · Updated July 17, 2026
Likely causes, ranked
Puncture in the tread
A nail or screw picked up on Rockford’s construction-season roads, plugging its own hole imperfectly. Found in minutes with a water dunk test, and properly repairable if it’s in the tread face.
Corroded bead seat
Salt-country special: aluminum wheels oxidize where the tire seals against the rim, letting air seep out slowly. Fixed by dismounting, cleaning, and resealing — no new tire needed.
Leaking valve stem or TPMS sensor seal
Rubber stems age and crack; TPMS sensor grommets loosen. Cheap fixes that masquerade as mystery leaks.
Temperature drop, not a leak at all
Tires lose about 1 PSI per 10°F — a 50-degree Illinois cold snap “deflates” every tire in town and lights up TPMS dashboards across the county. If all four dropped together in October, that’s physics.
What to do right now
- 1
Don’t just keep topping off — underinflated tires flex, overheat, and wear their shoulders fast; they also brake and corner worse.
- 2
Look for the obvious: a screw head shining in the tread. Don’t pull it out — it’s currently the plug.
- 3
Bring it in for a dunk test. Puncture repairs run about $35 and take half an hour; bead reseals and stems similar.
What it typically costs
Proper inside patch-plug repair ~$35 at Grote Auto Service. Bead cleaning/reseal or valve stem similar. TPMS sensors $65–$120 if one is the culprit. All far cheaper than the tire that fails from months of low-pressure running.
Our diagnosis fee goes toward the repair.
Related questions
Can a tire with a nail in it be repaired?
If the puncture is in the tread face, smaller than 1/4", and you haven’t driven it flat — almost always yes, with a proper inside patch-plug. Sidewall and shoulder punctures can’t be safely repaired; anyone offering to string-plug a sidewall is gambling with your family.
Why does my tire pressure light come on every fall?
Cold air is denser: roughly 1 PSI lost per 10°F drop. The first cold October morning trips TPMS lights all over Winnebago County. Top up to the door-placard pressure — and if one tire drops faster than the others, that one has a real leak.
What actually fixes it
If it turns out to need real work, this is what usually does it — with pricing published up front, so there are no surprises.
Prefer we reach out?
We respond within the hour during business hours — usually faster.
This guide describes common patterns, not a diagnosis of your specific vehicle — that takes an inspection. If your symptom is marked urgent, treat it as urgent. When in doubt, stop driving and call (779) 888-5000.
Stop wondering. Start knowing.
A proper diagnosis costs less than a wrong guess — and ours is applied to the repair.
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