My tire has gone flat.
Proper inflation is the single most important part of tire care.
It is not necessarily the right inflation for your vehicle. Always use the inflation recommended by the ve hicle manufacturer. You can find it in your owner's manual, posted on the edge of the driver's door, on a door post or on the inside of the glovebox door. Use a good quality tire gauge. It's natural for radial tires to have a slight bulge in the sidewall at their proper inflation pressure.