Most people who regularly check and top off the air in their tires usually go by the PSI indicated on the sidewall. That could be a mistake if the carmaker recommends a tire pressure that is lower than the maximum PSI that a tire is rated to handle. You can check the owner’s manual to ensure your vehicle has the optimal level of air pressure.nYou should visually inspect tires for possible damage to the tread or sidewalls while checking the air pressure with a pressure gage. If one or more tires is underinflated or has too much air pressure, you should take care it of right away.