One of the most common reasons for tyre pressure loss, and the main reason for a tyre losing pressure when there's no leak, is changes in the temperature of the outside air. Temperature changes affect tyre pressure because of air's nature – contracting when it's cooled and expanding when heated.
Valve Stem Leak
Flat tires aren't always caused by a hole in the rubber. Instead, a malfunction or leak in the valve stem can be the culprit. The valve stem is the part of the tire that you unscrew when adding air. Any damage or even dirt on this small piece could cause your tire to lose air until it's completely flat.
Remove the valve core on the wheel where the tire loses air slowly by inserting the removal tool tip into the stem and rotating it counterclockwise. If you see signs of corrosion, make sure to clean the stem before installing a new core. Screw a new core in place and pump the tire up.
If your tire continues to lose air after being filled several times, just bring your car in for a repair or replacement.
If the leakage is slow, you may be able to continue driving for several hundred miles before you think about changing the tire. However, if the puncture is severe, you'll likely need to replace your tire immediately before driving on it further. Learn more about how car insurance covers tire damage.
Replacing your valve stem is an easy task to do, even if you aren't a mechanic. New valve stems cost about $10 dollars to repair if you do it yourself. If you bring it to the shop, it will cost about $30.
It is not recommended that you drive with a leaking valve cover gasket, as this can lead to overheating and engine insufficiency, as well as extensive engine damage.
A good test to check for valve stem damage is to so spray soapy water on the stem while gently flexing it, and see if any air bubbles are present. If bubbles are present, that means air is leaking out.
For every 10-degree drop in temperature, your tire loses 1 PSI. If the temperature drop is significant, air pressure could plunge, resulting in underinflated tires in the morning. This situation usually occurs when the daytime temperature is between 70 and 80 degrees and the night temperature drops to 30 or 40 degrees.
All car tires lose air over time, and there are normal and abnormal causes for it. The normal causes are: Osmosis (permeation). Temperature change.
If a thorough inspection of a leaking tire, which will probably require removing it from the vehicle, doesn't find a nail or puncture, the slow leak could be caused by a pinhole in the tread or sidewall.
If you are experiencing low tire pressure on top of other driving issues, you may have a problem with your wheel structure or a bent rim. When a wheel or rim is bent, it has the capacity to let the air out of your tires.
One of the most common and frustrating issues even for safe drivers is pothole tire damage. Depending on the impact, it can cause the sidewall to blow because of the sudden shift of air in the tire. You should avoid squeezing it since it can cause a tire puncture and flat tire.
The 4psi rules states that “if your tyres are inflated correctly then the tyre pressure measured when the tyres are hot (after travel) will be 4psi greater than the pressure measured when they were cold (before travel)”.
Ideal Tire Pressure
Tire pressure between 32 to 35 PSI is most suitable for most vehicles. However, one can go as low as 20 PSI (although that is not recommended). Anything below 20 PSI is considered a flat tire.
The most durable ones are reinforced metal valves, which can be freely replaced once every second seasons, rubber equivalents should preferably be replaced every six months. This habit will significantly increase your driving safety.
You CAN continue driving! The purpose of the air valve cap is to keep dirt and debris out and to keep air inside in case the air valve ever does leak (you can find out if it is leaking by spraying some Windex on the valve and see if it bubbles).
Valve stem seals often last more than 150,000 miles under normal driving conditions. Infrequent oil and filter changes may cause valve stem seals to fail prematurely. Improper installation often causes valve stem seals to fail shortly after installation.
Will leaking valve seals harm an engine? Not immediately and directly, however it does immediately and result in increased wear on the rods, increased oil consumption, and lower engine power. However you can run with worn seals for a very long time and it can be very expensive and time consuming to fix.