Temperature ChangesSudden drops or rises in temperature can cause your tire pressure to fluctuate pretty dramatically—typically, one to two pounds (psi) for every 10 degrees in temperature change. So, theoretically, your tires could lose 4 PSI if the temperature drops by 20℉ over a brisk autumn weekend. And if you're tires are old or worn, they'll be particularly vulnerable to these fluctuations. Before getting a replacement, you should try inflating your tire to the proper psi as listed in your drivers' manual, or on the inside of your drivers' side door and monitor it for about a week. If the pressure stays the same, you're likely in the clear! If your tires are still losing air, there are two technical problems to consider: valve stem failure and mounting problems.
PuncturesPunctures result from sharp objects on the road like screws, nails, or glass which create a hole in the tire. Punctures typically damage both the tread and the inner liner causing the tire to lose pressure. If you notice that one or more of your tires continuously loses pressure, or you discover a screw or nail in the tread, you should call your mechanic immediately. If your tire becomes underinflated it may be unsafe to drive on it, and doing so could damage peripheral parts. Thankfully, most punctures can be patched by a skilled technician—and save you hundreds.
Are your tires deflating faster than normal? Read more about the damage caused by cuts, punctures, and impact.