Are valve stem caps important?
This type of cap protects from dirt and moisture and also helps prevent air from escaping from a slightly leaking Schrader valve. ... If you take your vehicle in for a routine service that includes checking the tire air pressure, the valve stem caps should be properly tightened, and should be replaced if missing.
Can you drive without valve caps?
Even though you will be fine to drive with a missing air valve cap, we recommend replacing it when you get the chance so that you can keep dust and debris out of your tires. ... Metal caps can corrode over time and fuse to the stem, and removing it will become extremely difficult when you need to refill your tires.