another hvac question
#61
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Sorry for the constant posts...i just checked the 4wd line from where it connects to the small black T (took t off) to actuator on firewall. Leaked 5 psi over 20 mins...line is fairly new about a year old
#62
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Naa don't need pix. The purpose was to make sure the 4WD was not leaking, and it's not. The reservoir is not leaking either. Back in post #50, did each color hold vacuum AND move the respective doors?
#63
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With post 50, when i applied vacuum to each, it did seem to operate the doors properly with tiny bit of ait comin out pf the wrong vents..where mentioned "light". I just took a ride around the block. ...auto 4wd 2hi 4hi and 2low all switched properly. I also checked the line going to 4wd actuator itself by plugging one end and applying vacuum to other..it held vacuum so we can rule that line out
#64
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That's good, but did each color hold vacuum at the mode switch connector, (directly to the vacuum line)?
#65
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Yes, the only line that slowly leaked was brown and yellow....but 3psi over 10 minutes but you noted that wasnt anything to worry about
#66
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I'm just double checking here, please humor me
If you connect the vacuum pump directly to the line under the hood that goes directly into the dash, (no check valve, no Tees etc) and apply vacuum, it won't hold vacuum?
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If you connect the vacuum pump directly to the line under the hood that goes directly into the dash, (no check valve, no Tees etc) and apply vacuum, it won't hold vacuum?
#67
#68
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Check all of them again just for grins, and keep track of the results. Some modes will take some serious sucking to get vacuum down to 20", others will suck down rather quickly.
#69
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will double check tmr, it did leak on just the plastic line entering the cabin on off and bi level today, i was trying to trace it down to what was and wasnt
#70
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You have checked all of the vacuum lines at the mode switch connector, and they all checked good, (this also checked the actuators). You checked the plastic line from under the hood to the mode switch connector, and it checked good. If it leaks vacuum on any position when testing from under the hood, the mode switch is definitely the problem.