Intake Manifold Pressure
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Racer
Joined: Sep 2000
Posts: 255
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Intake Manifold Pressure
Could someone point me to a detailed explanation of the factors affecting manifold vacuum pressure?I'v been driving for the past 18 months with a boost gage added when the Procharger was installed so
I'm constantly aware of the pressure.I find it hard to determine what influences the reading.Aside from the general observations that when it's very hot,the reading is <-20" & that when it's very cold,the reading is between -10 & -4''.The car seems to run fine,no codes.The only thing I've noticed recently that if I come up suddenly to stop for a light,the idle drops down below 500 rpm,sometimes threatening to stall & then bounces up to its usual reading of 820 +/- 10 RPM(I have a digital tach).
I'm constantly aware of the pressure.I find it hard to determine what influences the reading.Aside from the general observations that when it's very hot,the reading is <-20" & that when it's very cold,the reading is between -10 & -4''.The car seems to run fine,no codes.The only thing I've noticed recently that if I come up suddenly to stop for a light,the idle drops down below 500 rpm,sometimes threatening to stall & then bounces up to its usual reading of 820 +/- 10 RPM(I have a digital tach).
