The term describes the absolute pressure within an engine’s intake manifold. This measurement represents the pressure relative to a perfect vacuum and is typically expressed in units such as kilopascals (kPa) or inches of mercury (inHg). For instance, a reading of 100 kPa indicates that the pressure inside the intake manifold is 100 kPa greater than a perfect vacuum. This value reflects the air density and the amount of air entering the engine cylinders.
The pressure measurement serves as a crucial parameter for engine control systems. It provides essential data about the engine’s load and air intake, enabling precise adjustments to fuel delivery and ignition timing. Accurate monitoring and control, informed by these pressure readings, leads to improved fuel efficiency, reduced emissions, and optimized engine performance. Its utilization evolved alongside the development of sophisticated electronic engine management systems, allowing for more responsive and adaptable control strategies.
