'98 Astro fan blower issue...

I have a 1998 Astro and the vent (dash) will not blow. The defrost and the floor work great. This will not work with the AC as well as the heater. The fan is fine and blows strong for the floor and defrost. I hope this is something I can fix without having to take it to a shop. Any info will be appreciated.

Sounds like a very similar problem to what I am having... (the post about the blower/fan issue on '98 GMC Safari).

Does yours blow properly through the top vents at all? Mine is "intermittent" but appears linked to application of the gas pedal.

Likely the vacuum line is loose or broken from the engine to the vent control switch. Pull the engine cover off and check to see if the vacuum line has a problem. I believe it runs from the left side of the engine up to the dash. It's a fairly common problem and easy to fix, check other posts for more info.l

Sounds like a very similar problem to what I am having... (the post about the blower/fan issue on '98 GMC Safari).

Does yours blow properly through the top vents at all? Mine is "intermittent" but appears linked to application of the gas pedal.

my blower works perfect on the defrost and floor settings. It is strictly the vent or dash vent.

Likely the vacuum line is loose or broken from the engine to the vent control switch. Pull the engine cover off and check to see if the vacuum line has a problem. I believe it runs from the left side of the engine up to the dash. It's a fairly common problem and easy to fix, check other posts for more info.l

thanks for the info. I have a 94 Astro as well and have had the dog house off that one a number of times. My 98 which I'm having the blower issue has a conversion package. I have never needed to take the dog house off this van. It looks a bit different. I will certainly give it a try.

Likely the vacuum line is loose or broken from the engine to the vent control switch. Pull the engine cover off and check to see if the vacuum line has a problem. I believe it runs from the left side of the engine up to the dash. It's a fairly common problem and easy to fix, check other posts for more info.l

ggcatt -- any thoughts on my issue? It seems similar, in that initially that hose was disconnected. Now that it's be reconnected, it doesn't blow through the top vent when I hit the gas pedal hard. When I let off on the gas pedal, it starts blowing back through after about 4-5 seconds.

Thanks,
Steve

sjmetz, likely you have another vacuum leak somewhere. When you hit the gas, the vacuum builds in the inlet manifold, and the leak increases, loosing vacuum to the blower position control. When you let off the gas, the vacuum leak decreases to the point that the blower position works again. It's hard to pinpoint these leaks, but a vacuum pump and gage may be helpful. Most mechanics or autozone have them.

I am an owner of a 1998 Chevy Astro with rear heat and rear air. My problem was only cold air out of the rear heat and only the front defrost vents worked and the temperture selector not switching for hot to cold. I will try to be as detailed as possible. Lift the hood, and look at the large black box on the top left side of the engine. Just behind the AC reservoir, there is a vacuum line attached to the large black box on top right side, that looks like a Tee fitting with three connections. One went to the float switch on the bottom right of the larger black box near back, the other goes straight down to the vacuum ball located on the frame of the vehicle (underneath). The last is a thin vacuum line that looks like an electrical wire. Pull on all three lines one at a time. If one pulls all the way up to you, that is the broken one. The thin vacuum was broken in half on my Astro. The fix was to remove the air filter tube (the 3" flex tube that goes to the backside of the air filter box). Once removed, look for a flexible black tubing about a 1/2 inch round that should look empty because your line is broken. Pull the tubing to reveal the other half of the hose and reconnect with tubing that will fit over the thin black wire. Not sure what size, but what I did notice is that this was probably the same problem that GM fixed before when the vehicle was under warranty because my line looked repaired but was broken in a different spot. Before I reinstalled the air box tubing, I did wrap the entire flex tubing line with aluminum foil to help block the heat. I am not a professional, but I tried this and it worked for me. Good luck. This. feels like the scene in Independence Day when they figured out how to bring down the spaceships in the sky. Good luck