- Joined
- Mar 9, 2010
- Messages
- 464
Rohan said:Ah, suddenly someone is talking absolute pressures.
The vacuum gauge on the dash on most cars will commonly report 750+ mm of vacuum, in normal driving.
Descending hills, or decelerating from speed will pull this much vacuum.
Thats getting not that far from a complete vacuum.
Not that anyone here has ever mentioned achieving a complete and utter vacuum anyway...
Pretty much everything that is OBD-1 compliant or newer that uses a MAP sensor instead of an airflow meter will give a reading in absolute pressure. There are even 2 (at least) Commandos on this forum that do as well. Where I live my Range Rover reads 98KPa wide open or not running, not zero. No type of piston pump is going to get close to zero, ever.