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)
Anywhere from 18 to 21 inches. is normal.
It must be connected to a full-time vacuum source such as the intake manifold.
from the vacuum source in the intake manifold,to various vacuum operated components
from the intake manifold.
If you mean specifically, what type of vacuum, the answer is manifold vacuum. Manifold vacuum is constant and doesn't, change with throttle valve opening, the way ported vacuum does.
you need manifold vacuum for the brake booster.. (intake manifold)
In a normaly aspirated gasoline engine manifold vacuum will be 18-20"hg at sea level. you will drop approx. 1"hg manifold vacuum for every 1000' in elevation.
Most likely a vacuum leak. Check vacuum lines, throttle body and EGR valve. Also the #1 reason is the intake manifold gasket leak. It needs to be replaced.
the vacuum comes from the intake manifold
There is no vacuum canister on this vehicle.
There are many. All hoses get their vacuum from the intake manifold. (plenum)
Take a vacuum hose off at the intake manifold and put a vacuum gauge on the port, then read the vacuum with the engine running.
That engine should have 18 to 21 inches of vacuum at an IDLE. You can find a vacuum source on the intake manifold.
17 TO 19 INCHES AT A IDLE. 18 to 21 inches at idle, and the above answer is close enoungh too.
The vacuum hose on the civic is going to be to the left of the intake manifold.
bad vacuum hoses or leaking intake manifold gaskets.
Directly behind the intake manifold: between manifold and firewall.
A MAP sensor is an anacronym for "Manifold Absolute Pressure" sensor. The sensor has a vacuum line going to it from an intake manifold vacuum port. It senses the amount of intake manifold vacuum or pressure depending on how far open the throttle (your foot) is when you drive. Wide open throttle-foot to the floor, dictates low vacuum in the intake manifold. This device is all part of your engine electronic control devices/sensors used to make your engine run at peak efficiency and perform its best.
Most all of the vacuum lines will start from the intake manifold in the rear..........
Your 1993 Ford Escort has many vacuum hoses. They all originate at the intake manifold. Trace all of them back to the intake manifold.
Follow the main vacuum coming from the intake manifold and it will right next to the vacuum check valve......
"While Oreck was probably the first lightweight vacuum, there are now other vacuums that are eight pounds. Hoover, Electrolux, and Roomba have products that are also eight pounds."
On the sbf windsor manifolds, there is a threaded hole behind(toward rear of manifold) where the carb goes. You will need to screw in a vacuum tree there. As a basic rule of thumb, vacuum lines will always attach to one of the manifold runners that lead to the intake valve(s). Also...pretty much all carbs have vacuum ports. The ones in the base plate are full vacuum, while the ones in the body are usually ported or timed vacuum( like for dist advance). Bri On the sbf windsor manifolds, there is a threaded hole behind(toward rear of manifold) where the carb goes. You will need to screw in a vacuum tree there. As a basic rule of thumb, vacuum lines will always attach to one of the manifold runners that lead to the intake valve(s). Also...pretty much all carbs have vacuum ports. The ones in the base plate are full vacuum, while the ones in the body are usually ported or timed vacuum( like for dist advance). Bri
As with any internal combustion engine, the vacuum leak can be anywhere on the intake side, including intake manifold gasket, cracked intake manifold, EGR valve, throttle body gasket and even the vacuum operated devices can contribute to leaking, such as the vacuum assisted brakes or vacuum operated vent system. Starting fluid can often be helpful when searching for a vacuum leak; search the likely places, listening for the the typical hissing sound. Once you find a place that you suspect of the leak, spray a little of the starting fluid. When the starting fluid hits a vacuum leak the engine RPM's change slightly. Good luck.
It installs between the turbo and throttle body in the intake piping. It installs with hoses and clamps. It has a vacuum line that connects to the manifold that open the valve when the throttle closes and vacuum is present in the manifold.