Pressure of the intake pressure sensor output characteristics

Pressure of the intake pressure sensor output characteristics : EFI engine intake pressure sensor used to detect the intake air injection system called D-type ( speed density type ) . Intake pressure sensor detects intake air is not as direct as the intake flow sensor detection , instead of using indirect detection , but it also is affected by many factors, and thus the detection and repair , there are many different Cooling Temp Sensor intake air  Cooling Temperature Sensor  price place , the resulting failure also has its particularity. Operation of the engine , with the change in the throttle opening degree , the intake manifold vacuum , absolute pressure and the output signal characteristic curves were changed. However, changes in the relationship between them is how ? Output characteristic curve is positive or negative ? This problem is often not easy to be understood, so that some maintenance personnel at work there is a " not sure " feeling. D-type injection system is detected in the rear throttle valve inside the intake manifold absolute pressure .Throttle rear reflects both vacuum and reflects the absolute pressure , so some people think that the degree of vacuum and absolute pressure is a concept that , in fact, this understanding is one-sided. At atmospheric pressure under the same conditions ( standard atmospheric pressure of 101.3kPa), vacuum manifold higher , reflecting the manifold absolute pressure , the lower the degree of vacuum is equal to the atmospheric pressure minus the manifold absolute pressure difference of the values. The manifold absolute pressure higher , indicating that the degree of vacuum within the manifold lower manifold manifold absolute pressure equal to the outer atmospheric pressure minus the difference between the degree of vacuum . Ie the atmospheric pressure is equal to the vacuum and absolute pressure and . Understand the atmospheric pressure , vacuum, absolute pressure relationship, intake Engine Temperature Sensor output characteristic to clear.Operation of the engine , the throttle valve opening degree is smaller, the intake manifold vacuum greater manifold absolute pressure is smaller, the output signal voltage is smaller. Greater the degree of throttle opening , intake manifold vacuum is smaller, the absolute manifold pressure is greater , the output signal voltage is greater. The output signal voltage and the vacuum manifold is inversely proportional to the degree of (negative characteristics) , and manifold absolute pressure proportional to the size ( positive characteristic ) .