need vacuum help asap
#16
i went outside and i pushed in the motor under the hood that the white line goes into and it didnt switch the a/c or anything, stayed the same. does that mean anything? vacuum lines are so confusing!
according to that other link posted above it oculd be the motor under the dash? the guy said his was working when he pressed on that which is what mine is doing. i might try and pick those up. anyone know where i could get one at?
according to that other link posted above it oculd be the motor under the dash? the guy said his was working when he pressed on that which is what mine is doing. i might try and pick those up. anyone know where i could get one at?
#17
If the diaphragm is bad in the vacuum motor then yes that would be the same a broken white vacuum line.
Why the white vacuum line causes this is it lets air in and then you have no vacuum. It has nothing to do with the position of the vacuum motor in or out.
You are moving the vacuum motor by hand under the dash and that will tell you nothing.
You need to put a hand vacuum pump on the lines of each vacuum motor and see if they hold vacuum or not. Also see if you are getting vacuum on the black vacuum line with the gauge on the vacuum pump.
You can rent a hand vacuum pump at most auto part stores.
#21
alright im still stumped.
everything from the vacuum check valve to the motor side is good! its the other side of the valve that im looking at now. how am i to go about checking these lines? i know everyone says to go and use a propane torch or whatever but the vacuum check valve is supposed to keep vacum from going back toward the motor so i dont see that happening? how do i check these. ive got the vacuum diagrams printed out but their kind of confusing to read.
everything from the vacuum check valve to the motor side is good! its the other side of the valve that im looking at now. how am i to go about checking these lines? i know everyone says to go and use a propane torch or whatever but the vacuum check valve is supposed to keep vacum from going back toward the motor so i dont see that happening? how do i check these. ive got the vacuum diagrams printed out but their kind of confusing to read.
#22
Do not use a propane torch or other sprays for finding vacuum leaks on this vent system, they are for checking the the engine gaskets.
As the diagram shows the vacuum line runs from the vacuum tree on the upper intake to the vacuum check valve.
From the vacuum check valve it goes to a "T" and from there one vacuum line goes to the vacuum tank on the side of the heater box.
The other black vacuum line from the "T" goes to a inline vacuum splice and then a hose and another inline splice and then it goes to the vacuum selector control valve on the dash.
Now you go to an auto parts store and rent a hand vacuum pump with a gauge on it. When you take it back you get your money back or you can buy it as it does not cost very much.
Check the vacuum line from the "T" to the vacuum tree on the upper intake manifold and make sure it is OK.
Now unplug the vacuum plug off the vacuum selector control valve on the dash, the one with 5 vacuum lines on it.
Put the vacuum pump on the plug nipple that has the black vacuum line on the other side. Pump up the vacuum and see if it holds. If it does not hold then work on the vacuum lines back to the engine.
If it holds vacuum then pump up vacuum on the other nipples one at a time until you find the one that does not hold vacuum and fix the vacuum line or its vacuum motor.
If all the nipples hold vacuum then replace the vacuum selector control valve on the dash.
As the diagram shows the vacuum line runs from the vacuum tree on the upper intake to the vacuum check valve.
From the vacuum check valve it goes to a "T" and from there one vacuum line goes to the vacuum tank on the side of the heater box.
The other black vacuum line from the "T" goes to a inline vacuum splice and then a hose and another inline splice and then it goes to the vacuum selector control valve on the dash.
Now you go to an auto parts store and rent a hand vacuum pump with a gauge on it. When you take it back you get your money back or you can buy it as it does not cost very much.
Check the vacuum line from the "T" to the vacuum tree on the upper intake manifold and make sure it is OK.
Now unplug the vacuum plug off the vacuum selector control valve on the dash, the one with 5 vacuum lines on it.
Put the vacuum pump on the plug nipple that has the black vacuum line on the other side. Pump up the vacuum and see if it holds. If it does not hold then work on the vacuum lines back to the engine.
If it holds vacuum then pump up vacuum on the other nipples one at a time until you find the one that does not hold vacuum and fix the vacuum line or its vacuum motor.
If all the nipples hold vacuum then replace the vacuum selector control valve on the dash.
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