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Fix a car tire that loses air

We'll check the valve stem, tread, and bead—or tell you when to take the tire to a shop for repair or replacement.

Troubleshooting · Home appliances
15–30 min
What you'll need
  • Tire pressure gauge
  • Soapy water (spray bottle)
  • Valve core tool (optional)
  • Replacement valve core or valve stem (if needed)
Step 1 of 8

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Steps

Goal: Confirm the leak, then check the valve stem, tread, and bead.

  • Check the tire pressure when cold. Check again after a few days or overnight.
  • Good: The pressure drops—leak confirmed. Proceed to Check valve stem.
  • Bad: Pressure stable—no leak.

Check valve stem

Goal: Rule out a leaking valve stem or valve core.

  • Inspect the valve stem for damage. Tighten the valve core with a valve core tool. Spray soapy water on the valve stem and look for bubbles.
  • If the valve leaks, tighten the core or replace the stem. A tire shop can replace the stem quickly.
  • Good: No bubbles at the valve. Proceed to Puncture and bead.
  • Bad: Valve leaks—fix or replace the valve stem.

Puncture and bead

Goal: Find punctures and check the bead seal.

  • Inspect the tread for nails, screws, or objects. Spray soapy water on the tread and bead area. Look for bubbles.
  • A puncture in the tread can often be plugged or patched. A puncture in the sidewall cannot be safely repaired—replace the tire.
  • A leak at the bead may require reseating the tire or cleaning the rim—take to a tire shop.
  • Good: You found and fixed the leak. The tire holds pressure.
  • Bad: Puncture in sidewall, or cannot find leak—take to a tire shop.

When to get help

Call a tire shop if:

  • You cannot find the leak (dunk test can locate it).
  • The puncture is in the sidewall.
  • The wheel is damaged or the bead will not seal.

Do not drive on a severely underinflated or flat tire.

Verification

  • The tire holds pressure when checked over several days.
  • No bubbles at the valve stem, tread, or bead when tested with soapy water.
  • No check engine light or tire pressure warning (if equipped).

Escalation ladder

Work from the device outward. Stop when the problem is fixed.

  1. Confirm symptom Verify the tire loses air with a pressure gauge.
  2. Valve stem Check the valve stem and core.
  3. Puncture Inspect the tread for punctures; use soapy water test.
  4. Bead and rim Check the bead seal and wheel rim.
  5. Call a pro Tire shop for repair, patch, or replacement.

What to capture if you need help

Before calling support or posting for help, have these ready. It speeds everything up.

  • Which tire loses air
  • How fast the tire loses air (slow or fast)
  • Valve stem condition
  • Whether a puncture was found
  • Steps already tried

Does the tire lose air over time?

Check the pressure when cold. Check again after a few days.

Check the tire pressure with a gauge. Note the pressure. Check again after a few days or overnight. Good: pressure drops—leak confirmed. Bad: pressure stable—no leak.

Yes No

You can change your answer later.

No action needed

The tire holds pressure. No further action.

Done

Does the valve stem leak?

Spray soapy water on the valve stem. Look for bubbles.

Inflate the tire. Spray soapy water on the valve stem and valve core. Look for bubbles. Bubbles: valve leak—tighten core or replace stem. No bubbles: check tread and bead.

Yes No

You can change your answer later.

Fix valve stem or core

Tighten the valve core. If that does not work, replace the core or valve stem. A tire shop can replace the stem quickly.

Done

Is there a puncture in the tread?

Look for nails, screws, or objects in the tread. Use soapy water to find leaks.

Inspect the tread for nails or screws. Spray soapy water on the tread and look for bubbles. Puncture in tread: can often be plugged or patched—take to a tire shop. Puncture in sidewall: replace the tire—do not repair. No puncture: check the bead.

In tread No or in sidewall

You can change your answer later.

Repair puncture or replace tire

Tread puncture: plug or patch at a tire shop. Sidewall puncture: replace the tire—do not repair. Do not drive on a severely underinflated tire.

Done

Does the bead or rim leak?

Corroded rim or poor bead seal can cause a leak.

Spray soapy water on the bead area where the tire meets the rim. Look for bubbles. Bubbles at bead: tire may need to be reseated or rim cleaned—take to a tire shop. No bubbles: leak may be slow or elsewhere—take to a tire shop for a dunk test.
Question

Does the bead leak?

Continue

You can change your answer later.

Call a tire shop

Take the tire to a tire shop for bead reseating, puncture repair, or a dunk test to locate the leak. Do not drive on a severely underinflated or flat tire.

Done

Reviewed by Blackbox Atlas

Frequently asked questions

Why would a tire lose air?
Common causes: damaged valve stem, puncture in the tread, corroded or damaged wheel rim, or poor bead seal. Check the valve stem first.
Can I fix a tire that loses air myself?
Yes, for valve stem replacement and some punctures. Sidewall damage or bead leaks often need a tire shop.
When should I call a mechanic for a tire that loses air?
Call a tire shop if you cannot find the leak, the puncture is in the sidewall, or the wheel is damaged. Do not drive on a severely underinflated tire.

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