Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

GMC Safari/Chevy Astro Heating / Cooling



  • cobcob Posts: 210
    I got my hose from the dealership. I then routed it over the plastic air intake to keep it cooler so it would not melt again. I guess they make repair kits for the hoses but it is a cheap part even at the Chevy dealer. You can get the doghouse out without removing the seat I have done it a few times. You have to move the seats back all the way and pull the cover straight back. When you lift it out you will have to compress the corner of the seat cushion to squeeze it by and it takes alot of jimmying but it will come out. Putting it back on is a little easier.
  • tkwtkw Posts: 29
    I placed an order at the dealer this morning and picked up after lunch. It was surprisingly cheap, under $10 CAD. I tried 3 autoparts store to try to get longer ones so that I can reroute it out of harms way without success. I know you have to get the whole assembly from the dealer with the end fittings and afraid that it may be in the range of $50. How often you can get away with $10 from the dealer?
    The downside is the re-routing option will be limited by its pre-determined length (800mm). I read it here that a fellow member has replaced his from under the hood. I will try my best not to touch the doghouse. I did it last weekend and it really sucks!
    Anyway, thank you for your help and wish me luck!
  • tkwtkw Posts: 29
    Hi guys:
    A big thank you for all of you here who shared their experience. Here's my update.
    I replaced this vacuum hose thing from under the hood this morning with some difficulty. But it is doable if you have small hands like me. At one point, I almost have given up and attempted to take the dog house out. From under the hood, first I removed the air filter, air intake housing and the electrical connectors. Then I picked up the old hoses piece by piece on the manifold and traced it to near the back of the A/C compressor. I had the rubber fitting held between my left index finger and middle finger and stuck there. I didn't have any room to get my thumb on it to pull it out. I wondered it'd help if I have all thumbs. ;)
    To avoid wrestling with the dog house, I reached in and removed the wing nut securing the metal bell housing over the throttle body. This gave me an extra inch or so to pull the rubber fitting out. The new hose from the dealer is barely long enough to allow rerouting over and away from the engine. And now that we finally have dash A/C, it is raining out there today.
    Sorry for the long post. To keep the record straight, this so call vacuum hose is actually a vacuum signal tube for HVAC control. Its GM part no. is 15967970. It is 1/8" O.D. x 800 mm long. I hope this would help those who has this nagging problem.
  • wmrherewmrhere Posts: 1
    In 2 words - vacuum line.

    I have a 97 Safari which has had the same problem. The factory supplied tubing is less than 125" O.D., and runs from the top of the manifold about 20 - 30 inches. In my case it was glossy black and really brittle after heat exposure. I ultimately replaced the entire length, after 2 unsuccessful problem area replacements.
  • cobcob Posts: 210
    I have a 1997 that is a conversion van by Glavel. The rear heat/a/c was installed by them at an aftermarket company. There are freon lines and heater hoses running to it so I would assume it would work for both a/c and heat. However the control for it is just a 3 speed fan switch. The unit always blows warm air no matter what temp I have set on the dash control. The a/c portion is an extra evaporator connected to the factory unit and there is a sticker under the hood that states they put in x amount of freon at this company. My dash factory a/c blows cold (so I know that the freon is not leaking)but the rear one blows warm air. Is there a valve somewhere in the system that may be stuck for the temp control to the rear unit? If there is where can it be located? If anyone else has this setup or has some answers please reply, thanks.
  • ClairesClaires Chicago areaPosts: 1,222
    cob, you might also want to bring your questions to the folks in the Climate Control Problems: All Cars Forum to see if they have any answers for you.

    ClaireS, Host
    Coupes & Convertibles | Vans & Minivans


    Need help getting around? - or send a private message by clicking on my name.

    Tell everyone about your buying experience: Write a Dealer Review

  • tkattkat Posts: 1
    Look here for the Vacuum hose issues on your AC, it may just be cooling your feet, as the diverter is not getting any/enough vacuum. As to the wiper motor, unbolt it partially, and clean the copper grounding strap you'll find on one of the mounting bolts. It's a poor combination of two dissimilar metals, and corrodes after about 5-7 years. Result: no ground, no wipe.
  • jpc47jpc47 Posts: 62
    Turned out to be a melted vacuum line going to the ac control. My mechanic spliced a piece in and now I'm fine.
  • Just last week my 96 astro will only blow air out of the defrost and floor, like it is stuck on that setting even when i try to make it blow out of the dash vents.

    Where do I even start to fix this problem???

    Thanks allot!
  • cobcob Posts: 210
    Look back a couple of pages and you will see many posts on this issue. It is a common problem that the plastic vacuum line from the passengers side front of vehicle by the a/c components that runs across the engine to a vacuum port on the drivers side of the motor. The line melts and you lose the air settings. It is a cheap part and try to route the replacement line over the plastic air intake so it doesn't melt in the future.
  • rrc60rrc60 Posts: 1
    I recently had same problem. Fix was made by replacing vacuum line from manifold to A/C condenser box. The climate control valves are run by vacuum. Most likely you have a small vacuum leak.
  • 13tigger13tigger Posts: 1
    I have a 95 GMC Safari Van that I can't keep the relay working. The lower fan speeds go out, I replace the relay in the duct. All speeds work then for about 6 months then I need to replace it for the same reason. Does anyone know why I can't keep relays? Thanks 13Tigger
  • demaziiidemaziii Posts: 1
    There is a valve on one of the tubs coming from the compressor,it has a black cap,it is approximately 1" high, remove the black cap (unscrew cap to remove) to get to the valve (you can open or close valve with a flat screwdriver)
  • cobcob Posts: 210
    I found the valve. There were 3 different valves with black caps on them. One looked like the spot to fill the freon with a valve stem in it. Another one looked like a check ball in it for possibly discharging the system. The third on one of the lines had a stem sticking up about 1 inch that was round and came to a square at the top which could be turned with a wrench. I tried turning it left and right but it did not move either way. I did not want to put too much pressure on it fearing I would break it and let all the freon out. Is this the correct fitting? If so what is it supposed to be doing? If I turn it does it allow the freon to go through the line to the rear unit? Does it balance the pressure between front and rear? I could use some more input if you have any thank you. FYI while on a 5000 mile road trip last week when I had the dash control set on max a/c sometimes the rear unit would blow cold air especially when it was cooler out but, when we were in the southwest it just blew hot air from outside 100-115 deg.
  • pzmompzmom Posts: 1
    My air-conditioning quit blowing out into the cab low to high in Max A/C, A/C, or vent mode. Defroster works (blows cold air). Rear A/C works (I understand they are two different systems). I can hear the blower running. I checked the fuses, but they seem to be okay. I can't find anything in the manual on how, what, or where to check. Any ideas? Thanks!
  • I just fixed this same problem on my 2000 Astro last night. The vent system is vacuum operated and a vacuum leak will cause the symptom you have described. The most common cause on the Astro/Safari is a cracked vacuum line that runs across the top of the motor towards the front. The vacuum line is exposed to high heat continually and gets brittle and begins to crack in numerous places. The reduced vacuum causes the A/C vent selector to not operate properly. The vacuum line has 90 degree rubber elbows at each end and the rest of the line is very small diameter plastic tubing. One end it accessible under the hood on the left side near the A/C equipement, the other end is accessible if you pull the engine cover and is on the driver side of the intake manifold. I just replaced the whole vacuum line with rubber vacuum host and rerouted it off the top of the engine and put some shielding on it. HTH
  • tkwtkw Posts: 29
    There're lots of discussions on this subject on recent posts. What eharston posted is correct except that the entire job can be done from under the hood. It is a bigger job to remove the dog house than the actual repair. I found it out the hard way. You don't want to mess around with it.
  • machicjmachicj Posts: 2
    i have a '99 astro and yesterday the rear a/c blower quit. i checked the fuse, (#12) and it looks fine. also checked the a/c relay under the hood, but don't know how to tell whether its good or not. any suggestions? thanks
  • The Blower on my 1994 Astro will not blow on "High". The A/C Compressor remains engaged even though the fan doesn't blow. I replaced the Blower Control Switch in the dash thinking that would fix the problem. $29.00 later...the blower still will not blow on high. I am not an electrical whiz when it comes to trouble shooting . Any tips would be helpful before I go out and buy a resistor, fan motor,...a new van?
  • iwhiteyiwhitey Posts: 3
    I have an ac problem that I can't seem to find the answer for. Basically, the compressor won't shut off in any position of the vent dial, even if it's off or the heat is on. Any ideas?
  • rayj3rayj3 Posts: 1
    I have a 95 astro van with dual a/c ,my blower motor stops on all speeds for a short time and starts up after a minute or less.Can someone tell me where a relay or thermal fuse could be located for this intermittent problem.I already replaced the blower motor since new.
  • bymechbymech Posts: 1
    I have the opposite problem, My rear a/c factory install blows cold air, my front vents blow warm air. Anyone have any suggestion,will be greatly appreciated
  • davet2davet2 Posts: 1
    under the front hood remove the air box and u can see the small hard vacuum line where it has been damaged. One inch of rubber hose can connect the ends and a/c will return to blowing out every vent.
  • tkwtkw Posts: 29
    Thank you but I had it replaced & rerouted a while back. When that small vacuum line got brittle with engine heat & age, it just disintegrated in many pieces. Splicing was not an option in my case.
  • i have a 96 astro awd with rear heat, the problem is i am not getting any heat. The blower is coming on but no heat is coming out only blowing cold air

    please help winter is here.
  • :cry: i really hope someone can talk me through fixing my heater problems. i bought my van a year ago and up until now i have had only the high setting on my heater and only works on defost. now that it is cold out the heater has totally stopped. i tapped the blower motor housing and it started up. did this 3 times and then nothing. now i have to drive around with the windows down just so the front windsheid stays somewhat clear. can someone please tell me if it is a fuse or the blower motor itself. thank you
  • 97xpresso97xpresso Posts: 249
    It spunds like you have two separate problems. Your blower moter is probably shot, and the vacuum line that controls the vents is rotted. (you can search the fix for the 2nd problem earlier in this Astro board.)
  • Check resistor board located behind fluid reservoirs just to the right from blower motor. Disconnect plug and undo two screws holding it in place. Remove by pulling it out (can be little hard because of some sealant around). Check for burns. Repair if you can, or replace it.
  • I had the same problem as yours. My fan only worked on HIGH while on DEFROST.

    Here is my solution:

    1) Check your blower fan relay, located on the firewall above the blower fan compartment. Mine was OK. I had to remove some corrosion from the wire connector pack. Spray occasionally with WD40 to prevent further corrosion.

    2) Check your blower fan resistor pack. It is located on top of the AC/blower fan compartment. Mine was rusty. I cleaned it with some sandpaper and a wire brush. If yours is really bad or burnt out, replace it, otherwise it can be cleaned with no problems.

    3) If your fan doesn't work at all, replace it.

    4) If cleaning the connections doesn't help, and your fan still only works on HIGH while on DEFROST, then your fan switch and wire harness connector in the dash are no good. REPLACE THESE AS A PAIR. My switch and wire harness connector were melted. When a blower fan is failing, it draws more current than normal, causing the wires and switch the heat up at the point of connection. This melts the plastic and makes an even poorer connection. I bought a used switch and harness at an auto wrecker for CDN$5. After solder-splicing each wire and carefully taping, everything works just great.

    If you replace the switch and wire harness connector, IT IS VERY IMPORTANT TO REPLACE THE BLOWER FAN MOTOR ALSO, otherwise the switch and wires will melt again because the motor is failing.

    Make sure to check a few vans at an auto wrecker for a good switch and harness connector. I had to look at about 5 vans before I found one good enought to buy.

    Hope this helps. Good Luck.
  • Please let me know if you can help me with this matter.
    @ 90 degree Fahrenheit as soon as turn on the AC, temperature gage climb all the way to red the zone. After turn of the AC, temperature goes back down.
Sign In or Register to comment.