Quote:
Originally Posted by wagonman76
The map sensor is manifold absolute pressure. I was wondering if it might actually measure the differential between manifold vacuum and atmospheric pressure. If so, then I was wondering if changes in atmospheric pressure could throw the map sensor off a bit, possibly in our favor. I believe a barometer measures atmospheric pressure and rain is way on one end of the scale.
Any thoughts?
|
Wagonman,
Yes you are correct. MAP sensors do measure the difference between the manifold vacuum and atmospheric pressure.
The info sent to the ECU helps determine the fuel volume supplied BUT there are also other factors like engine temp , intake temp , etc.
In addition the ECU in most cases has a range built in so it compensates for altitude , weather , various quality of fuel , engine wear etc so the drivers don't have to.
Yes also to the barometer observation They measure only air pressure and the writing on the gauge tells of rain , sunny , change etc.
Cheers , Pete.