1999 buick limited
#21
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I will try your diagnostic of the vacuum lines, I suspect it might be the control head, some times i get air to come out of the vents and then sometimes not, thank you for your help
#22
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True Car Nut
Mine only had 5 lines, so there are none missing.
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cliff (06-28-2016)
#23
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I was able to check the vacuum tank and I did hear a hissing noise from the the tank when i took the vacuum line off of it and also had a good draw of suction from the line, so I am good up to this point, my next move will be to check the purple line under the dash to see if i have any suction at that point
#25
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I was able to check the vacuum tank and i could hear a hissing noise from the tank, also I had a good draw of suction from the line itself, i was not able to pull off the dark blue line from the cluster of colored lines behind the glove box, i did locate the dark blue line that goes to a diaphragm up behind the unit and took it off the diaphragm turned on the car, started the the ac put it on MID waited awhile but felt no suction, if i could get the dark blue line off of the cluster of colored lines then i would be able to see if i have any vacuum there, do you have to take the box off to get at the lines????
#26
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vacuum lines
I believe there are only 5 lines........
I never liked this set up......reason why? where the vacuum manifold lines, attaches.....I believe there is a 7 or 8 mm nut holding the manifold on....for test purposes, you remove the nut, and pull off the manifold....and then with a vacuum pump(manual), you can apply vacuum to each one of the lines to see if the individual actuator moves.....here'* the problem....there are small tubes that fit into each vacuum line.....sometimes they break off, causing a vac leak.....sometimes when you try to pull the manifold off, the manifold may stick to one of the tubes and breaks off when when you try to pull off the manifold after removing the nut.....
Question is, is there enough vac at the purple line, to operate the actuators? A vac gage or pump would verify this.....
You can also grab the manifold lines and give a slight tug on each line....if you hear a hissing noise, chances are one of those stubs is broken....
I never liked this set up......reason why? where the vacuum manifold lines, attaches.....I believe there is a 7 or 8 mm nut holding the manifold on....for test purposes, you remove the nut, and pull off the manifold....and then with a vacuum pump(manual), you can apply vacuum to each one of the lines to see if the individual actuator moves.....here'* the problem....there are small tubes that fit into each vacuum line.....sometimes they break off, causing a vac leak.....sometimes when you try to pull the manifold off, the manifold may stick to one of the tubes and breaks off when when you try to pull off the manifold after removing the nut.....
Question is, is there enough vac at the purple line, to operate the actuators? A vac gage or pump would verify this.....
You can also grab the manifold lines and give a slight tug on each line....if you hear a hissing noise, chances are one of those stubs is broken....
#27
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I was able to get vacuum at the tank and the line going to the tank, I also was able to get to the light purple line and disconnect it from the orange splice and i got vacuum there as well, that light purple line goes to the cluster of colored lines that goes to the hvac programmer box, therefore like you mentioned it is either the programmer box or the control pane, I have heard if the control panel was bad it would be flashing on the display, once again thank you very very much
#28
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I was able to get vacuum at the tank and the line going to the tank, I also was able to get to the light purple line and disconnect it from the orange splice and i got vacuum there as well, that light purple line goes to the cluster of colored lines that goes to the hvac programmer box, therefore like you mentioned it is either the programmer box or the control pane, I have heard if the control panel was bad it would be flashing on the display, once again thank you very very much
#29
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apparently you have to take the programmer out and open it up to get to the inside, also the harness with the colored lines have tabs on it and it looks as though you need to pull out the box anyway just to get to the tabs. in some discussions concerning the clear plastic harness it seems to be a problem with them getting soft over time and it causes a vacuum leak and that clear harness is not available to get a new one
#30
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apparently you have to take the programmer out and open it up to get to the inside, also the harness with the colored lines have tabs on it and it looks as though you need to pull out the box anyway just to get to the tabs. in some discussions concerning the clear plastic harness it seems to be a problem with them getting soft over time and it causes a vacuum leak and that clear harness is not available to get a new one