What is the standard value of intake manifold pressure?
1 Answers
Intake manifold pressure, more accurately referred to as the absolute pressure value of the intake manifold, generally ranges between 40-80 KPA. When the engine is operating, the intake manifold pressure will be lower than atmospheric pressure due to the suction effect created by the downward movement of the piston during the intake stroke. The intake manifold pressure is influenced by the throttle opening, engine speed, and sealing performance: the smaller the throttle opening, the greater the suction effect during intake, resulting in higher intake manifold suction, greater vacuum, and lower intake manifold pressure; the higher the engine speed, the greater the suction effect during intake, leading to higher intake manifold suction, greater vacuum, and lower intake manifold pressure; better sealing performance results in higher intake manifold suction, greater vacuum, and lower intake manifold pressure. The intake manifold is typically made of plastic and is prone to damage during vehicle use. Once the intake manifold is damaged or cracked, air leakage will occur. Air leakage in the intake manifold can produce audible sounds, and the vehicle may experience shaking, unstable idle, weak acceleration, and easy stalling. Severe cracking can even prevent the vehicle from starting. When air leakage is detected in the intake manifold, it should be promptly inspected and repaired at a repair shop. Generally, a leaking intake manifold will be directly replaced with a new one.
