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GMC Safari/Chevy Astro Heating / Cooling



  • tfinkastfinkas Posts: 1

    If you could please send me that diagram for the 97 Safari/Astro vacuum tube routing I would greatly appreciate it.

  • r0eninr0enin Posts: 1
    I was wondering if you got a copy of that diagram? if so could you send it to me? have a leak in my 99 and come to find out that is the line that goes to the rear a/c, it came loose from the connection that was used to bolt it away from the exaust and was resting on the cadalitic converter and melted the aluminium. Thanks
  • rkstammrkstamm Posts: 1
    What canister did you use, and how did you add it in?
  • miekym2miekym2 Posts: 1
    edited July 2011
    hey there.. Is there any way you can send me a copy of the vaccum diagram also ? I'm having issues with my girlfriends astro ac and it would help me a great deal.. Thanks Mike
  • jim481jim481 Posts: 4
    No matter which position I set my air control knob air only comes out the defrost vent of wind shield. Also when I move air control knob to MAX A/C blower motor does not increase speed.
    Hope someone can give me some help on this issue and maybe someone has a vacuum diagram they could email me.
  • I can tell you exactly what the problem is, as I have fixed this on, 3 seperate work vans. It's a broken plastic vacuum line. If you lift the hood, and look just above the alternator, you should find it. I just usually get a 12" piece of 1/8" rubber vacuum hose, from Napa, break out the brittle section of plastic, and use the rubber line, to rejoin.
  • jim481jim481 Posts: 4
    Thanks for your reply.
    I do see a broken vacuum line as you describe but where is it connected too??
    Their is a couple lines coming through the fire wall and the broken one is attached to like a 90 degree ell but where is the other end???
  • Sorry about long reply. Have been away from puter, for awhile. The other end goes off to your right, under the air intake, and across the top of the engine, on the driver's side. You almost have to reach inside there and feel around for it. I found loosening the 2 air intake clamps, unplugging the connectors, and removing the intake, made it easier to repair the line.
  • Thanks for your reply.
    Can you give me a little more info on what I am feeling around for?
    A pic would be great.
  • Cant do a pic, as I would have to remove the upper air filter cover, and air intake, which requires what I mentioned before, just to take a pic. Snap up the 2 clasps for the air filter, loosen the 2 hose clamps, unplug the 2 electrical connectors, and remove this assembly. The broken end of this plastic vacuum line, runs over top of the rad hose, and underneath, what you have just taken off. Remember, this line goes all the way to the rear of the motor, but even if it is broken, it should all still be there, to see. Don't feel around, trying to find the other end, remove what I said, and you'll find it.
  • vp79vp79 Posts: 1
    I found a break in my hose coming off the condenser. The problem I am now having is that the end of the hose disconnected from the intake area/ place near altenator and I am not sure where to look to put it back. Can you tell me the specific area I need to look or what it is I am looking for?
  • Hope you fixed it but if you didn't.... The problem may be in two places. The first and easiet is the manifold located on the left side facing the engine. It is located to the right of the black box. One line goes through the firewall, one goes down, and one goes across the top of the engine. In my case, mine was badly worn on the down part and the one going across the engine. There should be no problem fixing the one next to the black box. The other one is an issue if you don't know where it is. There are two ways to get to it.

    If you know how to remove the engine cover, you'll have better access to the manifold. The manifold is right on top of the valve cover. If it is broken off, it's a little tough to see it. Just keep looking for a black vaccume that has one hose coming from the valve cover about 1/2" into the unit. The other side has the fitting. Be very careful taking off the hose, you don't want to break off that fitting. I took the fitting off and cleaned out the broken part. I then used a small piece of hard tubbing and joined it with the tubing I bought at the auto store. I bought about 6" more then I needed so I could move the line away from the heat.

    The other way. If you can reach the air cleaner screw, remove the air cleaner assembly. Look for the aluminum tube running in front of the vlave cover. Right behind that you'll see the vaccume. The line has a right angle on it. If you can pop off the vaccume line, you will be able to repair the line. I used a section of the hard vaccume line as a coupler. it worked just fine. I hope this helps. I know I had a difficult time becuse I did not know where the vaccume was located. Once I found it, It took about 10 minutes to fix it. The car is blowing through all vents in all settings.

    One other note. I did have to change out the resistor located in the blower housing. The number one plug was burned up. I figured the vaccume line failed which caused the resistor to overheat. That was a $65 part. Not to difficult to change and located behind the wiper and coolent tanks. Just pry the plastic plugs up from the top. You'll see a small groove. The black plug comes all the way out and just lift out the tanks after making a few disconnections. Remove the two screws holding the hoses, then the two screws holding the resistor. You just have to disconnect the wire on the left. It resistor will comes right out after taking off the two screws.
  • Hi Gang,
    I've searched all the threads..seen some reference to rear heater not blowing hot....but found no solutions.
    Rear heater and AC blowers\speeds work fine, heater does not blow hot and AC does not blow cold. Front heat is all good on speeds and functions, etc.
    Any suggestions on how to troubleshoot and fix rear heat problem would be appreciated.

  • Hey did you ever figure out the vacuum line and were it goes. I have the exact same problem and I can't find were it goes to save my life. I had the inside engine cover off, the air intake off and the throttle body cover off, still can't find were it plugs into. The hard plastic vacumm lines that go from the A/C and over to the valve cover are all fine. It's that same soft rubber hose that was just dangling there and dry rotted as dry rotted can be. it's about 14 inches long. I've been to a hundred web sites and they all refer to the hard plastic lines...gahh it's frustrating as I'm a pretty good back yard mechanic
  • Hi all,

    I have a 96 chevy astro van that has a climate control without a/c. The interior knob broke off
    so I went and got a replacement controller, but it also has an a/c turn on it. I got it installed but
    it is not working. Do I have to get a climate control without the ac attachment or should it still work. Any advice would be great. Going to take apart and give it another shot. Thanks
  • Hi,
    I posted a query back in November about the rear heater blowing air fine on all speeds, but the air is cold. I flushed the rear heater core, but still just cold air. Would there be a vacuum-controlled valve that regulates the ratio of hot coolant to the rear core somewhere?? Any info or ideas would be greatly appreciated.

  • Well, I managed a temporary fix for my own problem and thought I would share it, in case others have the same problem. Just to the right of the black heater box , below the silver AC condenser/drier you will find a solenoid with upper and lower 5/32 vacuum hoses. The upper one comes from the firewall, the lower one goes to the valve that controls hot coolant to the rear heater core. Apparently the solenoid stuck closed last summer due to lack of use.
    So I disconnected the two hoses and connected them directly with a 90 degree 5/32 connector. I now have hot coolant going to the rear heater core all the time which can be regulated with the rear heater fan switch. Van is a 97 GMC Safari AWD, but I believe this would work for all model years.

  • 2000dcastro2000dcastro Posts: 1
    edited February 2012
    Can anyone tell me how to get to the heater core on a 2000 astro van, please. I have a coolant leak under the passenger dashboard and that seems the logical problem.
  • I have a 91 Safari, and it's just a matter of a few screws to take out on the plastic dashing on the passenger side.. should be pretty simle to get to.
  • Did you ever get this figured out? I have the exact same problem in my 91' Safari?
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