Step 1 : Introduction to the question "5. What does the acronym PSI stand for when referring to automobiles?"
...1. Passed Safety Inspection 2. Plush Soft Interior 3. Pounds per Square Inch 4. Paradigm State Ignition The "Pounds per Square Inch" or "pound-force per square inch" is a unit of pressure or of stress. It is the pressure resulting from a force of one pound-force applied to an area of one square inch. This is very common in the automotive industry to determine tire pressure. Over- or under-inflating tires can have a critical effect on an auto's performance, handling, and fuel efficiency. PSI guidelines in the U.S. are usually available on the tires themselves as well as information provided in the vehicle owner's manual.
