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If you unhook the line from the vacuum pump to the vacuum tree on the fire wall and hook a gauge straight to the pump line, what are you getting for a vacuum reading.
If that number is higher than what you have off the tree connections you have a leak in one of the lines.
If that number is the same as you have at the tree and it is only going to 17, your vacuum pump is starting to get weak.
My guess of what might have happened is that an air vent door on the a/c was stuck open and you may not be getting the proper air flow thru the heater core....so when you moved your actuator, it corrected itself...as for not hearing the changes of vacum controled vents, it doesn't matter as long as the air goes according to the actuator...I hope this is the end of a cold truck.
During my lunch break or when i get off of work i will retest my vacuum as Dave said. I was getting 17 psi from the vacuum booster line so ill check before the tree connections. I will also take a peek at my switch and the connector and try to inspect as much of the line as possible. Thanks for all the help and ill get back to you guys at the end of the day and report what i have found.
Well i retested my vacuum pump before the tree and after the tree and im getting an even 20 psi. It went up 3 psi from the summer. So i tryed my air direction settings again and nothing. So i put the vacuum pump line directly to the small lines that run to the cab and moved the switch around and still nothing. In fact there is just as much vacuum in the cab when i had everything attached normally. It is holding suction so i think i have a blockage somewhere in the line. What do you guys think?
It is throwing heat like crazy still ever since i messed with the actuator.
I bought one at the stealership several years ago, I don't think it cost much, but cant recall how much! Check out the price of new, may be cheap enough to gust change it out once you have the dash all ripped apart to get it out! LOL
Well before i decided to go with another switch i started to play with the vacuum. I took the main line coming straight off of the pump and attached it to the T. All of a sudden everything worked. So i checked all of the lines in the engine compartment and nothing is leaking. I was told that my master cylinder is no good in a previous post and i just got the part today. I have a spare vacuum booster (new) and i will install that at the same time. I also pulled my dash apart around all of the vacuum lines and still couldnt find any leaks. If changing these components do not work then i will change the switch. Unless there are any more ideas.
This is an awesome site. Too bad i didnt find it sooner. Thanks guys.
Last edited by dieselbogging; Jan 4, 2007 at 11:41 PM.
Not trying to be a smart alec, just for the record: Vacuum is not measured in PSI. In the US auto industry is is measured inHg (inches of mercury), just take a look at a vacuum trouble shooting gauge.
Well everything is working now and i havent replaced the vacuum booster yet(Ill do it anyway). Could'nt find a pinched line or leaking line anywhere so im guessing my vacuum booster is the problem. Thanks for the tip on how vacuum is measured. By the way my name is not alec haha.
Thanks for the help.