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GMC Safari/Chevy Astro Heating / Cooling

123578

Comments

  • sdrorisdrori Member Posts: 4
    Hello
    My vacuum lines are dead. The ball is broken and I have no idea where to start? Is there a place where I can find a diagram of the vacuum lines and also where can I buy new lines to replace the old ones? What happens in my car (94 safari 4.3l) is that the heating and cooling goes to the defrost position when I accelerate and I have no cruise control. The ball is there but not connected to anything. Any help would be appreciated.
    Shai
  • breezibreezi Member Posts: 1
    I have a 95 Astro I bought last year, high milage, in January heater blower would work sometimes but most of the time not. From what im getting from this sight that could be the vacuum lines.Would that not being fixed lead into other problems? Yesterday headin back to work on lunch van started to make noises then a burning smell. I got it back to the work lot and there it sits.I have never seen it over heat and although it was smouldering something it never lost any fluids. Seems to be coming from the pulley's. One person took a quick look and suggested that it is the A/C compressor?
    I'm really hoping for a less expensive answer if there is one. Found this sight last night and want to say thanks to all that help with the good advise!
  • tstormtstorm Member Posts: 10
    Sounds like you have two problems. The blower motor not working is not the vacuum lines. When the vacuum lines crack you can't control where the air goes but the motor still blows air... usually only out of the defroster. I'd say that your blower motor is dying and or the resistor/wiring harness is burnt.

    I have had a car in the past that had the A/C compressor freeze up so that is possible... I've not had your second problem with with my Safari... I did have to replace a blown serpentine belt at around 80,000 miles tho...
  • rab23465rab23465 Member Posts: 9
    The heater produces heat and also cool air when in the AC mode. Problem is the fan/blower only works in the first two positions. When I turn the control to the high setting there is no response. If I leave the control setting there the fan will come on every once in a while but not stay on steady. Everything works fine in the low and medium settings. The rear heater and AC fan works fine. Cany anyone suggest what may be a solution to my problem.
  • duecekdduecekd Member Posts: 19
    I have had a '92 and now a '95 GMC Safari and this happened to both. On mine it was the fan relay switch located on the firewall inside the engine compartment above the blower housing on the passenger side. Go to your favorite parts store and have them show you which of the 2 relays mounted side by side it is. And it's cheap and easy to replace. The one I got for the '95 was a little larger in size than the original, so it didn't want to mount in the exact same spot, but with a little American ingenuity, I worked it out. They may be able to test your relay, and if that's not it, my next suspect would be the blower resistors. Again, they are located in the same area, I think mounted to the blower housing. You can test them with an ohmmeter, or if they're really bad, it will be quite obvious, since they will be charcoal. Again, ask the guys at the parts store. That's what they get paid for. Hope this helps, and good luck.
  • 4damndogs4damndogs Member Posts: 1
    hi i have a 1998 astro awd with f&r air and heat. today i had the air on high setting, and the blower motor started making a humming sound. i know i have or had a mouse in the interior of the van but i dont think that would cause the blower motor to hum. is it on its way out or is there a way to tighten up the blower motor up. also the rear air does not blow, the rear heat blows (cold) so i know it is not the motor, i think it is the switch because i pulled the switch away from the dash and and if you juggle and twist it around enough it comes on. any ideas on eather one of the problems would be greatly appricated, i don't want to have to take it to the mechanic for things i can do my self. thank you in advance
  • beaubobeaubo Member Posts: 2
    02 Astro. Has about 75000 miles on it. After a car wash the fan stopped working unless you opened the hood and tapped on the blow motor housing or slammed the door really hard. What could this be? Is it the resitor? How do I get to anything in there? I'll keep searching but it's getting really hot outside and I don't want to put the new baby girl in the hot van at all! Help!!!!
  • tstormtstorm Member Posts: 10
    The resistor is behind the radiator overflow and the windshield wiper fluid resivour. It sounds like you may have a bad connection, maybe try cleaning the connection at the resistor and at the blower motor. The blower motor is hard to get to... it has a plastic cover over it which needs to be cut.
  • beaubobeaubo Member Posts: 2
    I'll give that a try myself as I believe a mechanic did this for me some time ago. Maybe they didn't. Best to do it yourself!
  • iambytemeiambyteme Member Posts: 1
    I hope this will help ,I am surprised with all the "techs' here no one has a heater vacuum diagram for a Safari to share out well heres my diagram for all to use
    gmc safari vacuum diagram
  • charleywadecharleywade Member Posts: 1
    thank you very much.that tubing almost fell apart in my hands.i connected the two together with a piece of plastic tubing,and my controls were restored. :D
  • bdarbdar Member Posts: 19
    Hi everyone,

    I was lucky enough to find this forum online and I must say that this has been an extensive discussion into the chevy vacuum line issue. I am very familiar with this as I have run into this problem twice now with my 97 chevy astro and each time I have replaced the lines myself with lines that I have made, and it has worked great. However, I seem to be having a little issue that I wanted to run by everyone.

    The problem started when I had an issue with the car jumping/shaking while idle. So I took it to the Chevy dealer for an inspection and they told me the Fuel Injector/Spark Plugs/ Distributor Cap, Rotor, and Spark Plug Wires as well as Engine Oil Pressure Sensor was bad. They wanted to charge me $1,900 and I was like h*** no, and so they gave me the car and i went out and bought the parts for $350 and I did the job myself and it works great now. However, when I got it back from the dealer after the inspection, the air was not coming out of any of the vents on any setting.

    The suspect area is the 3 way adapter behind the accumulator where the vacuum line connects in from the intake manifold. The vaccum line was fine, but the problem is there are now only two tubes connected to that adapter. The first one is the vaccum line from the intake and the second one is another tube that is a little to the left on the accumulator on the firewall. However, the third port is open and there is suction on it. The issue is that I don't remember from when I was fixing the vacuum tube if there is a thrid line that is supposed to connect there. What I did was I put a vacuum cap on that open side of the connector and so the air comes out now and works,, but it doesn't come out as stong as it used to be before I gave the car to the dealer. I was wondering if anyone has any idea about that. I would really appreciate it! Also, the line that is coming out of the firewall is worn out and crumbling and I wanted to get that replaced, but I don't know where that goes into.

    Basem D.
  • duecekdduecekd Member Posts: 19
    bdar, check out my posts #124 & #126 in this forum. It has info on what I did mixed in with other stuff to rerun the vacuum hose that goes in the firewall from the "T" connector. Might as well do it now before winter hits, because you know it will fail when it's zero outside! Good Luck!
  • bdarbdar Member Posts: 19
    Hey duecekd,

    Thanks for re-directing me to your previous posts. I read them and they did help me to find the vacuum ball when I was under the car. What I found is that there are 3 tubes going out from the Firewall. The first tube is the degraded rubber tube that is going into the t connector that I had mentioned. The second tube is a hard plastic thin tube that goes into a round device right under the accumulator, and the third tube is also a hard plastic tube that runs all the way down to where the vacuum ball is and it connects on an adapter port to the top left of the vacuum ball. That third tube doesn't actually connect right into the vacuum ball.

    I felt the vacuum ball with my hands and I found another thin adapter port, but nothing is connected there. There is no tube or even a vacuum head from where a tube may have been there. I am thinking that maybe when i took it into the shop that the dealer may have unplugged the cable from the vacuum ball to the t-adapter and never put it back in the car. It wouldn't be difficult at all to run another tube from the ball up to the t-connecter, but is that what I am supposed to do? Once I get that sorted out, I will look into replacing the rubber tube that is going into to firewall to the green cable.

    Thanks,

    bdar.
  • bdarbdar Member Posts: 19
    Hey duecekd,

    Thanks for re-directing me to your previous posts. I read them and they did help me to find the vacuum ball when I was under the car. What I found is that there are 3 tubes going out from the Firewall. The first tube is the degraded rubber tube that is going into the t connector that I had mentioned. The second tube is a hard plastic thin tube that goes into a round device right under the accumulator, and the third tube is also a hard plastic tube that runs all the way down to where the vacuum ball is and it connects on an adapter port to the top left of the vacuum ball. That third tube doesn't actually connect right into the vacuum ball.

    I felt the vacuum ball with my hands and I found another thin adapter port, but nothing is connected there. There is no tube or even a vacuum head from where a tube may have been there. I am thinking that maybe when i took it into the shop that the dealer may have unplugged the cable from the vacuum ball to the t-adapter and never put it back in the car. It wouldn't be difficult at all to run another tube from the ball up to the t-connecter, but is that what I am supposed to do? Once I get that sorted out, I will look into replacing the rubber tube that is going into to firewall to the green cable.

    Thanks,

    bdar.
  • sdrorisdrori Member Posts: 4
    Hi everyone. The vacuum line seems to be an issue all of us are dealing with. I was wondering if maybe there is someone out there that can make a drawing that all of us and future generations can download and use. I know the manuals don't cover it. While on the subject, anyone has an idea where I can find a vacuum ball. Mine broke. :cry:
  • sdrorisdrori Member Posts: 4
    Hi I have a 94 safari that also needs new plugs wire.etc. May I ask where did you find all these parts for so cheap? :)
  • bdarbdar Member Posts: 19
    Hi sdrori and everyone,

    I wanted to apologize sdrori because I had seen you post earlier but I just now noticed that it was directed to me. First of all, in regards to the parts, this is what I did. Napa Auto Parts is the best place to get the vacuum tubing from. They have the hard and soft vacuum tubing (all different sizes) and it is about 0.49 cents per foot of tubing. If you need vacuum heads, connectors, and elbows, auto zone sells those for like $3 or $4 a pack and they come in a variety of assortments. As far as the vacuum ball, I haven't been able to find anyone who sells it except the Chevy Dealships. Some people have it on Ebay and what not, but it is not readily avaliable. My vacuum ball also broke and I bought one from the Chevy dealer for $35. You just go into the parts department and ask for the part for your model and year car. I assume since your car is a Safari, you would have to go to a GM dealership, but I am not sure about it.

    However, I also have a special treat for everyone!!! I know lots and lots of people asked for a vacuum diagram and I was finally able to get my hands on one (don't ask me what I had to do, LOL) But I have it ready to post, but how do I post images or files on the forum? Thanks!!
  • sdrorisdrori Member Posts: 4
    Great news about the diagram. Can you email it to me? srdbx@netvision.net.il
  • duecekdduecekd Member Posts: 19
    I was trying to send you the diagram to your email, and as shown here, it just comes up as undeliverable. I also tried to remove the .il at the end, but no good.
  • aquarian1000aquarian1000 Member Posts: 1
    Thanks for the vaccum diagram-I need the lines inside the engine compartment as well. Have repaired the one that crosses the manifold 3-4 times now have to replace it. Also rear heat is cold so I have to find that line too.
    Any info on the lines inside the engine compartment??
    Thanks
    BC
  • duecekdduecekd Member Posts: 19
    I have compared this diagram to my 95 Safari, and everything is there. I don't have rear heat, and I don't see in the diagram anything on it, so I can't help there. If you look at the diagram, #1 (vacuum source) would be from the back of the manifold to the ball, labeled #2, and #3 is the firewall. Everything below the firewall is in the dash. The numbers that are in the hexagons correspond to the chart below, and all attach to the back of the selector switch which controls your heat, AC, Vent, Defrost, etc. settings. The ones labeled #6 are the actuators that open and close the vent doors to the different vents in the dash & on the floor.

    You may have known all this before, but if not, that is my interpretation of the diagram, and I hope it helps. Keep in mind that any small break in the lines, especially from the manifold to the ball, and then from the ball to the selector switch, and nothing will work right. If you have to replace the main feed from the manifold, just make sure you get enough line to route it up higher in the engine compartment to keep it from getting hot again. Don't take the same route as they did in the factory or it's just going to burn up again eventually!

    Good Luck, and hurry, old man winter is just around the corner!!
  • astrovanfanastrovanfan Member Posts: 1
    Dear BDAR:

    Could you please e-mail the vacuum diagram to me at gerry@bablaw.com.

    Gerry
  • hepmehepme Member Posts: 1
    Bdar, I'm ready to tackle this headache and your schematic sounds just like the ticket I need before I totally mess this up. Would you mind emailing me your drawing to msfiske@verizon.net Thanks a bunch.
  • bdarbdar Member Posts: 19
    I am trying to replace the third vacuum line that goes into the firewall from behind the accumulator as that one has failed now, but I opened up everything and I don't see anything connected to the selector switch. The switch on my 97 Astro has a colored wiring harness connected to it and it runs all the way back into the firewall area, but I do not see any t-connectors or any area where the vacuum lines from the firewall connect. I have tried to pull on the harness a bit and all I get is more wire. I have a diagram where I can point out what specific vacuum line I need to replace, and I was wondering if I can email you the diagram to see if you have any idea how I could get to that line. Thanks!
  • mike_wallacemike_wallace Member Posts: 1
    Just wondering if I could get a copy of the vacuum diagram as well. I too am having problems with my rear heat on my '99 safari only blowing cold and my control selector switch not opening or closing vents. There doesn't seem to be any vacuum to the switch. Thanks.
    Mike
  • duecekdduecekd Member Posts: 19
    REFER TO POST #213 BY iambyteme. THAT IS WHERE I GOT THE DIAGRAM FROM. I AM WRITING IN CAPS, NOT TO BE RUDE, BUT IN HOPES IT WILL STAND OUT.

    I don't know how to post it again, and I think it requires a hosted site to get to, which I don't have. So go to link on post #213 in this forum, and save to your PC to print. Not that I would mind, but it's easier than emailing each individual that may want it.

    P.S. Thanks to iambyteme for posting it in the 1st place. Hats off, and hopefully for everyone else, vacuum on!!
  • duecekdduecekd Member Posts: 19
    bdar, send me what you have to kdandaf-junk@yahoo.com. In my van ('95) the line from the ball to the selector switch was very tiny plastic tubing that went into the wiring harness that on my van runs along the very top of the firewall. I don't know where it comes out and gets into the engine compartment, but in my case I didn't care because I didn't have vacuum at the selector switch to the green connector. So I replaced it with new tubing, tie wrapping it to the same harness, and then bringing it in right next to the spot where the cable to open the hood goes through the firewall.

    That was close enough to right behind where the selector switch is in the dash. You'll need to pull the doghouse to see where to punch through. I used a bit a little larger than the new tubing, and then wrapped with tape to help it from rubbing a hole in the new tubing where it went through the firewall. Refer to my post #124 for more of the same story.
  • bdarbdar Member Posts: 19
    If you would like me to send you a copy of my diagram, please post your email and I will be glad to send it to you.
  • Charlie_UTCharlie_UT Member Posts: 2
    Greetings,

    I recently faced a similar set of problems on a 94 Chevy Astro Van. I hunted down some vacuum leaks that ended up being caused by battery acid eating holes in some of the vacuum line tubes wrapped inside a major section of the underhood wiring harness. The simplest approach (in this instance) was to unwrap the entire affected section of the harness, which contained several vacuum lines as well as electrical wiring. Note that some of these vacuum lines can be hard to spot as they are about the same size as the wiring and colored similarly.

    If you decide to unwrap portion(s) of the wiring harness be certain to keep track of which wires and vacuum lines are wrapped together and the way each of the different bundles are routed and attached to the body. A roll of masking tape, a permanent marker, a pencil, some blank paper and a clip board will make doing so possible and easy. To do otherwise is to ask for really bad headache. Too, if possible, finish the job once you start it because it's so easy to loose track of (forget) exactly what goes where even if you only step away from the task over night.

    Inspect and repair the vacuum lines in question. And then, because the opportunity to do so happens to exist, carefully inspect all the wiring and connectors uncovered during the process and clean and repair those as well.

    Afterwards rewrap the harness in as close to it's original configuration as
    possible. It's wise to use the highest quality electrical tape available, such
    as 3M and Scotch. Doing so costs a little more but it best insures against
    creating other problems in the future. (And believe me when I say the last
    thing you'd ever want is an electrical short occurring inside a wiring
    harness.) Another tip is to make use of a product called "Liquid Tape", or a
    variation on that name. It's a liquid form of insulation that's painted on the
    wiring, providing both highly effective electrical insulation and
    waterproofing as well. This is also available from 3M/Scotch.

    When I'm done with the job and everything's dried out and been proof tested I spray it down good with WD-40 to help ward off moisture. (Besides don't the rule say, "If it's supposed to move and don 't WD-40 it, and if it moves but ain't supposed to Duct Tape it!")

    Best of luck,

    Charlie
  • bdarbdar Member Posts: 19
    Hi Charlie_UT,

    Thanks for getting back to me on this. I really appreciate it. i am sorry that I didn't get to respond back sooner, but it has been a busy week! From the vacuum diagram that I have, I took a look at things and it indicates exactly what you said, that the vacuum lines run into the wiring harness. But my question is, how do you get to the wiring harness?? Mine in my 97 Chevy Astro seems buried between the firewall and inside panel of the car and I cannot see a way to get to it. I checked beside the battery and I don't see anything visible as far as the wiring harness. There was one tube that I was looking to replace and it was sticking out of the firewall right beside the accumulator (it was a very short tube that I assume connects into another tube that goes somewhere into the wiring harness) and so I replaced it and although it helped a little, the air is just coming out weak and not like is used to before.

    So I assume that this is the problem that I have and I am just about ready to not care anymore about trying to do it myself. However, I truly think that this is ridiculous and I did talk to my attorney this week about possibly filing a class-action lawsuit against GM since it is clear that some many thousands of people have had the same vacuum line issue and I truly feel like there should be a recall on this or at least should have been. He is looking into it but suggested to me in the meantime to call up GM and inform them of the issue and just how many people out there are having the same issue and threaten to sue if they can't do anything about it and then see where it goes from there. I am not sure if that will get me anywhere with them, but it won't hurt to try and the worst that they could do is say we don't care go to H*ll.
  • robby_6ft5robby_6ft5 Member Posts: 1
    well if you dont mind can you try to send me the diagram for the vacuum you can try to send me it if you want it will surely com in handy for myself if it is to much trouble.
  • lanceoshlanceosh Member Posts: 3
    I had a problem getting the Heater A/C working properly in my 1998 Safari.
    Took it back to the dealer who put in a new control (The one with 3 holes attached) now I get all kinds of air to the various areas and I can get the A/C to work BUT absolutely nothing beyond a luke warm(cold) air when the heater is turned on. Living in Canada we need a properly running heater in our vans!
    Now the dealer is suggesting the thermostat may be stuck and wants to replace it (of course at my cost)
    Could this also be a vacuum problem?
  • duecekdduecekd Member Posts: 19
    I would say their right in checking the thermostat first (of course after you have checked your coolant level to make sure it's not low). You may be able to find out if it is the thermostat by following the top radiator hose to the engine block. It should be clamped to a domed housing that the thermostat is inside of (depending on your van, you may need to remove the air cleaner housing).

    With the engine running and up to temp, and making sure to watch out for the fan and serpentine belt, take a LARGE screwdriver or something else stout and tap on the outside of the housing. Give it a good tap, but don't hit it hard enough to break the housing. Note your water temp if you have a gauge on the dash, and see if it doesn't jump up after doing this. You may want to try a few times. I have had this work in a pinch, and if the thermostat does unstick (if that's a word) your heat should work better. If this works, it also means the thermostat does need to be replaced. Good Luck!!
  • rickardorickardo Member Posts: 1
    I have a 93 Astro van with 80,000 original miles. In the last 2 years I've installed 4 new GM heater cores, which keep springing leaks. I've also replaced t-stat, rad cap and anti-freeze. Anyone know what causes this failure? Also just this year the engine does not stay at temperature for heat. After start-up the temp will go up, stat opens and temp drops, but never gets high enough for heat again.
  • irobot49irobot49 Member Posts: 1
    the heat went out low and high didnt work now none of it works.had heat , only worked on the middle 2 settings now none of it works?
  • astro1994astro1994 Member Posts: 2
    1994 astro heater speed switch only works on high, (Put new switch in no luck, Have changed this before and it fixed it not this time) Now not so simple I have to elaborate alot, When I go from off to low theres a click underhood read on, Mode is stuck on blend I guess half defrog half floor or feet (Tried new mode switch from dealer no change) When I do turn blower on from off (Repeating) to low nothing but a click is all I get and the click is coming from drivers side (Oppsite blower fan and any relays that I' read about) Furthermore with fan speed on (Any) Setting) Otherthan high when I try to switch modes I hear a very simular click underhood with no results in cab, Modes don't change, Should I pay $ to be a member of this site like TotallyYamaha, I have a few parts too that are new can they be sold on here ?
  • astro1994astro1994 Member Posts: 2
    If I get help I will help others but U have to tell the (Whole) story otherwise it makes helping someone not possiable.
  • bpress54bpress54 Member Posts: 2
    my 93 astro won't blow air thru the dash vents, only thru the floor or defrost.even when the selector is set to vent, air still comes out of the floor and defrost vents. i pulled the control out of the dash and found one vacuum hose off. i put it back on, but that didn't help. after closer inspection, it appears that there may be some hoses missing. does anyone know where i can find a diagram of the vacuum hose routing? i don't want to take it to a mechanic because frankly, i can't afford it.
  • duecekdduecekd Member Posts: 19
    REFER TO POST #213 BY iambyteme. This diagram was the same as my '92 and my '95 but not the same as newer models, as we found out. Read through all the posts in here, and I'm sure you'll find a fix for your problem. You probably have a broken vacuum line in the engine compartment, as most of us have had, and there are instructions in here on what to look for and how to fix it. I know I have put up several. Good Luck!
  • rab23465rab23465 Member Posts: 9
    I have a 2002 van and the radio has a button on the front to switch from AM/FM to CD/AUX.
    My question is this: Can I hook up some sort of connection from the back of the radio to be able to connect an MP3 player with a 3mm stereo headphone jack connection to the radio in my van. I have another vehicle that has an aux connection which makes it very easy to connect and listen to an MP3 player.

    How do I get to access the back of the radio? Is there some sort of diagram that shows me the back of the radio? Thanks for any help.
  • mhatkinsmhatkins Member Posts: 1
    I just replaced the water pump on My 94 Safari, after replacing the EGR valve which was after replacing the MAP sensor. The H2O pump was leaking pretty badly from the top and bottom weep holes, so, I replaced it. During the problem with the H2O pump acting up, it also leaked a little bit from the rear heater core. I had to replace water every morning to the tune of 1 gallon a day. Replaced the H2O pump. Solved the leak under the hood. But now, the water leaks even worse out of the rear heater core with periods of alot of steam and very wet carpet. And I now have to put in 2-3+ gallons of water into the radiator and reservoir about every 30-40 miles. The van has a new belt and hoses. Have not checked the thermo yet, but I think it is fine. Is there ANY way to diable the rear heater in these vans? I'm thinking cutting the lines to the rear heater core and capping them off. The van was a multi passenger van, but is now used as a work vehicle. Rear heater is NOT needed or wanted.( Yes, the van has regular oil and filter changes every 1200 miles due to age and it is used to tow a trailer 6 days a week.)
  • capt_genecapt_gene Member Posts: 3
    2002 Safari. 6 Cyl. 130K-----There are several 'large' hoses in the engine compartment related to the 'controls'.... also some very small ones, one of which was cut/burned, and replaced. One of the larger ones at the same 'junction' (Passenger side, engine compartment') isn't connected, just hanging. Looks like the end came off of something ((instead of having been burnt?)) but I can't find any place it goes. Looks like the main 'air' in hose to the system but not sure. A photo of where it goes would be awful nice, but any help is great.
  • capt_genecapt_gene Member Posts: 3
    In my last post, 246, I had a hose I didn't know where it belonged...... Now, thanks to this site, I know where it goes (I think), the round ball, pass. side, down low...... Problem, I can't properly see it and can't feel a place for the hose to go.. Any suggestions? It just feels round. Going back to play but hope that if I don't figure it out someone will tell me what I'm missing or a way out of my dilemma.
  • eriklaneeriklane Member Posts: 16
    That round ball is where that hose terminates-there's a spot for it to connect, but its location, behind the mud flap in the right side wheel well is difficult to get to. I ended up just taking out the mud flap, then taking out the ball (had 1 metal screw) and then taking that ball topside, connecting it, and then just laying it on top of the motor-it just sits there, loose, but it dont go anywhere, and doesn't get into the fan...funny. Bad design...I wasn't gonna fish in there more than once-after I'd originally connected it, and then found it apart again, it is just not worth the time to have to dig around blind in there to find the spigot...hek with it.
  • dfethersdfethers Member Posts: 1
  • achilliesachillies Member Posts: 1
    This applies to Re: probably a vaccum hose [97xpresso] by cob, and I really have to thank you guys. I had been trying to figure this out for two years, and finally got it licked. I have a 97 GMC Savanah comversion van, and for several years it has had no A/C in the rear unit, only heat.. lots of heat. The front air and heat worked fine, but when switching between AC and defrost it took a minute to actually change air paths (from the vents to the defrost). I never connected the two problems, but since cob's problem was the same as mine, I followed his lead and found the vacuum hose behind the accumulator and routed across the engine to a spot behind the compressor and air cleaner. Mine has a tee behind the accumulator or evaporator. The tee has one "input" vacuum hose, the 1/8" solid kind, that goes to the control on the dash I think, one hose that connects to an actuator in the front for the "mode valve" I think, and one that goes to the rear temperature switch (or whatever it's called) behind the compressor and air cleaner. The spot that was leaking/crushed/deteriorated, was where it connected behind the compressor. I should have replaced the entire hose, but I had some extra play and it was just the rubber 1/4" kind, so I clipped off 3 inches of the end and re-connected it. Now I have rear A/C OR heat, depending on how the temp control is set, and when I switch the front between A/C and defrost it responds immediately. Thanks again.
  • putz3putz3 Member Posts: 1
    There were a lot of great tips here on the vacuum situation, so I'm adding mine.

    I replaced all the vacuum lines except the little skinny one leading across the top of the engine from the passenger side. That one had snapped and was brittle, but I could not reach the other end back in the engine compartment. I didn't have the time to remove the doghouse, so here is what I did:

    I had left over standard vacuum hose from doing the other replacements (about 10").
    I had some high temp silicone gasket sealer from Permatex.

    I removed as much of the brittle line as I felt I could and then smeared the gasket sealer for about 3 inches along the length of the remaining small tubing. I then slipped the standard vacuum line over both ends. Once done, I used a Q tip with a blob of silicone to dab on each end of the standard tubing.

    Voila! Sealed.

    I then loosely pinched some aluminum foil around the whole thing as a heat guard and put everything back together.

    Works fine.
  • mixman1885mixman1885 Member Posts: 1
    WE HAVE A 99 ASTRO VAN THAT WONT SEEM TO HOLD FREON, IVE REPLACED THE DRIER ON IT AS WELL AS THE ORIFICE, DONE LEAK TEST NOTHING FOUND, PULLED VACUUM ON IT AND RECHARGED AND IT ONLY HELD FOR 3 DAYS...ALSO IT WAS ONLY BLOWING COLD IN THE FRONT THE REAL STILL BLEW HOT...CAN ANYBODY HELP ME OUT HERE?
  • lvdavelvdave Member Posts: 1
    o.k. i'm going to replace my hose's but what i have and what they are selling looks different. the hose going to my the rear a/c has a crimped on hose, and the replacement hose has a screw on connection.
    i found one that what looks right but is for the wrong year.
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