4 tiny little plastic caps which cost of less than one dollar provide you with insurance that you can control your car in just about every situation you can normally expect to encounter.
These tiny little pieces of black plastic (circled in red on the right) which cover your tire's valves are frequently lost and never replaced. What many people don't realize is the without a cover, the valve is easily contaminated with dirt, sand, mud, water, oil, grease, and many other substances which miight be found on or near a road's surface.
If any contaminant enters the valve mechanism and is present when you add air, or test the air pressure, it could cause the valve to malfunction resulting in an air leak. If you're lucky it would be a fast leak which you would possibly notice almost immediately, but, more than likely it might produce a very slow leak that will leave you without sufficient air pressure at a critical moment -- possibly when you are far from air or a service shop.
Keep your valves safe, check and replace your valve covers whenever you notice one missing. Since they're so small and inexpensive, we'd like to encourage you to keep a couple of spares in your glove compartment at all times.
Some after-market sellers offer to turn these plain little necessities into elegant accessories to your car's wheels. There are an almost infinite variety of designs -- mostly all chrome-plated to add durability and a bit of flash to something that would otherwise be a ho-hum detail on your car. Do a search on the web for "valve covers" or browse in the wheel accessories section of your nearest parts dealer or automotive section in your favoritedepartment store.
Several innovations have been offered to deal with air pressure and valve covers. One of these is a valve cover which visually tells you if you've lost air pressure. It works by adjusting itself to the pressure in the tire when it is placed on the valve and shows a green color as long as the pressure remains constant. If the pressure drops by more than 3 pounds per square inch, the color turns red and you can see that that tire needs to have air added.
Another solution to missing covers is offered by a specially designed cap which cannot be removed without a special key. These are sturdy metal caps which will resist considerable abuse and safeguard your vehicle from vandals or other mal-intentioned persons who would remove your valve caps and deflate you tires without your knowledge or permission.
Avani Revolv Chrome Tire Pressure Valve Caps marketed by http://www.avanigroup.com
Also, you might find some other useful material in our consumer information page.
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