Definition:
All modern automotive engines use fuel injectors to deliver fuel to the combustion chamber. Varying load, speed and temperature conditions require adjustibility of fuel delivery, and that is accomplished through changes to injector pulse width.
It is simply the amount of time, measured in milliseconds (ms), a fuel injector stays open (delivers fuel) during a cylinder intake cycle. Typical injector pulse width for an idling engine at normal operating temperature is between 2.5 and 3.5 ms.
Pronunciation: fyoo-uhl in-jek-ter puhls witth
Examples: When an engine needs to make more power, the onboard computer delivers more fuel by increasing the pulse width of the fuel injectors.