Is the weather cold, and you’re wondering why one of your tires is flat? Undoubtedly, temperature fluctuations can affect the air in your car tires. You’ll likely encounter a significant drop in tire pressure when the temperature decreases, especially in a frosty winter.
But why is it that only one tire loses air in cold weather? While it’s normal for tires to lose air pressure in cold weather, a pressure drop in one tire could signify a number of issues. But don’t worry because you’re about to know the possible causes.
As a mechanic, I’ll explain why only one of your tires loses air pressure in cold weather. I’ll also explain the science behind tires losing air in cold weather.
Question: Why Tires Lose Air in Cold Weather
Typically, air in cold temperatures will condense and become denser. It’s normal for gasses to become compressed when temperatures drop.
So, when the air in your car tires gets cold, it condenses and takes up less space. The dense molecules move slowly in the tire, colliding less frequently or hard against interior walls. Dense air and less collision of air molecules will lead to a decrease in air pressure.
As the weather gets cold, your tires will lose about 1-2 psi for every 10°F drop in temperature. This drop results from the air getting compressed as the temperatures decrease. The good news is this temporary issue will rectify itself after driving for a while.
Driving makes the air in your tires warm, thus making the molecules move faster. As a result, the molecules will collide frequently and hard, increasing the air pressure. Similarly, as the weather gets warmer, you’ll notice the tire pressure going back to its optimal condition.
Question: Why Only One Tire Loses Air in Cold Weather
As discussed above, there’s nothing wrong with your tires losing air pressure when temperatures drop. But why is it that one tire is losing more air than others in cold weather? Well, in that case, these are the reasons behind this issue.
- Tire puncture
- Leaking valve stem
- Leaking tire bead
- Snow covers the tire
- Damage wheel rim
Answer: Tire Puncture
A tiny puncture could be the reason one of your tires is losing air in cold weather. Usually, a nail, screw, or sharp object might have punctured the tire while driving. In this case, you’ll notice that the affected tire loses air pressure faster than other tires.
When other tires regain their normal shape after driving, the punctured tire will continue losing air. When inspecting the tire, look for any foreign object that might have punctured your tire. You can repair the puncture if it’s less than 0.25” in diameter.
For a quick fix, use a sealant that will seal the tiny puncture and inflate your tire. However, if you have a torn tire or a large puncture, consider replacing it.
After fixing the puncture, avoid driving in areas that increase the risk of a puncture. Avoid roads with much debris, rocky areas, or near construction sites.
Answer: Leaking Valve Stem
Another reason one of your tires loses air in cold weather is a leaking valve stem. When in good condition, the valve stem provides a passageway for air when inflating or deflating the tire. It’s a one-way door designed to maintain optimal tire pressure.
Once inflated, the valve stem doesn’t allow air to escape on its own. It secures air in the tires with the help of the valve stem cap, valve core, and valve stem body. If one of these parts is faulty, air might escape.
So, if you’ve noticed a significant drop in air pressure on one tire, check its valve stem. You’ll want to look for signs like wear, damage, corrosion, or dirt. Clean the valve stem with silicone spray if it is dirty or corroded.
You should also clean the part of the wheel that meets the valve stem. Lastly, replace the tire valve stem if it looks worn or damaged.
Answer: Leaking Tire Bead
A tire bead refers to the edge of your tire that sits on the wheel rim. It’s thicker and more reinforced than other parts of the tire, allowing it to sit properly on the wheel groove. This part must be in tip-top condition to make a firm grip/contact with the wheel.
When you inflate your tire, the contact between the tire bead and wheel forms a seal, preventing air from escaping. But if this part is dirty or damaged, it can cause air to leak out slowly. This leak could be why your tire loses air pressure in cold weather.
If you suspect the issue stems from a leaking tire bead, take the tire off and clean any dirt or debris on the bead. You’ll need to replace the tire if you find signs of damage along this tire part.
Note: Don’t overinflate the tire to avoid putting too much stress on the tire bead.
Answer: The Tire is in the Shade
Is the affected tire in the shade or covered by snow? If so, this explains why only one tire loses air in cold weather while the rest remain still. Temperature affects how air behaves in the tires.
Check the other tires to see if they have direct exposure to sunlight or stand on warmer ground. Tires facing the sun won’t lose air pressure, unlike the ones on the cooler side. You’ll encounter this issue depending on how you park your car.
When the sun comes out, it’ll warm the tires up, thus increasing pressure. Thanks to the black hue, tires facing the sun will absorb heat faster and warm the air inside.
A tire that’s on the shaded side will appear flat due to the condensed nature of the air inside. Moreover, if the tire stands on snow, the air inside will condense and occupy less space.
Driving or parking your car where all tires get direct exposure to sunlight should help resolve this issue. You must, however, inspect the tire for signs of damage.
Answer: Damaged Wheel Rim
A damaged wheel rim can also cause one tire to lose air in cold weather. A bent or damaged wheel rim can leak air, leading to a flat tire. Unlike the other tires that regain optimal air pressure while driving, this tire will continue losing air.
Hitting a curb when parking or colliding with other objects can bend or damage your wheel rim. Moreover, driving with a flat tire, especially on bumpy roads, can lead to wheel damage. So, inspect the wheel rim to see if it’s the cause.
You can fix a bent wheel by pounding on the metal with a dead blow hammer until it regains its original shape. If the wheel looks damaged/disfigured beyond repair, replace it.
Question: How to Keep Tires From Losing Air In Cold Air
When installing the tire, put it the right way to prevent air from leaking. Avoid damaging the tire bead, valve body, and wheel. You’ll also need to clean the wheel rim if it appears corroded.
Then, take your car to a tire technician for wheel alignment. Remember that misaligned tires can cause uneven wear and air leakage. Below are other tips to help prevent tires from losing air pressure in cold weather:
- Inflate your tires correctly: When inflating your tires, check the manufacturer-recommended PSI to inflate them evenly. Doing so will help prevent over or underinflating your tires.
- Monitor tire pressure regularly: A tire pressure gauge will help you check the tires’ air pressure. As a result, you’ll know when to inflate or deflate the tires.
- Drive responsibly: Driving carefully will help prevent hitting curbs or other objects that might cause air to leak. You’ll also need to avoid driving habits that can cause premature tire wear or loss of air pressure.
- Check for leaks: Inspect your tires before driving to spot items that might have punctured your tires.
Final Thoughts
You now know why only one tire loses air in cold weather. If you encounter this issue, check your tire and wheel rim for signs of wear or damage. Luckily, you can fix some issues at home by repairing or replacing defective parts. If you can’t identify the cause of your tire losing air in cold weather, seek help from a tire technician.