Is it normal for a 1996 Saturn SL1 to only have 17 pounds of manifold vacuum?
according to my service manual, the manifold vaccum should be like this:
Intake Manifold Vacuum (no load) --- 51 - 21hg at idle
Air Inlet restriction (no load) Between air filter and Throttle body 20hg at 4000rpm.
51 - 21hg roughly relates to 25 -10 psi
I also found this:
Crankcase Pressure/vacuum -- No load positive pressure
standard 4in H2O at 4000rpm
Service limit 10in H20 at 4000rpm
never knew you would need a water scale to diagnose a car :(
... its all the information i could find
Just to add an important note.....vacuum will only be measuring in inches of water column....you will NEVER see vacuum measured in pounds for a car. This may be helpful to you if you are looking for a vacuum gauge and none of them use a pound scale. (It will also help when explaining your problem to a mechanic)
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