long time lurker

[dblwall]

Great forum here guys to go along with a great vehicle, the Astro. First one was a 1990 Astro, had for 14 yrs with no problems. Needed a bit more room so got a used 2000 three years ago also problem free until now. Nothing big, just the AC / heat vent control not operating correct lately.
Searching here has pointed me in the right direction, assuming it's the vacuum hoses.

Had too have it smogged today, passed with flying colors with 145,000 on it. While the engine hump was off I tried looking for cracked / loose hoses. Before I dig into everything is it usually the Black White Orange hose that goes bad? Or do I follow it thru the firewall and look there?

[gtkane]

Welcome aboard!

The coloured vac hoses are usually the "inside" hoses. The problem usually lies under the hood, where the line taps into the intake. You'll probably find a loose hose if you feel around a bit.

[Matrixx]

Hi dblwall

Welcome to the Forum

As gtkane stated, it's usually the black thin line that cracks under the hood. The most common one to crack which also has with mine a couple of times is the Black line running along the front of the engine from the drivers side intake manifold leading to the heater control valve located on the passenger side just under the heater core (black box).

This is the most common cause for the problem you now have. Also check and make sure the line hasn't fallen off the heater control valve itself located at the base of it, this has happened to me as well once before. I would also check the other vacuum lines if that one seems to be fine. Hope this helps, please keep us updated, Thanks.

[dblwall]

Thanks guys I'm half way there I think. The hard small line from the drivers side was cracked (actually broke in half) and thought that was it. Changed it and still no go. Found another line, not sure where it goes. The line with the red arrow is what I replaced. The one with the blue arrow I can't seem to find where it goes. Only thing I see is a hard black plastic ball underneath the heater.

[Matrixx]

Hi dblwall

One line goes to that hard plastic ball and the other line goes to the heater control valve (on the bottom of it). Hope this helps. Please keep us updated, Thanks (Thanks for the picture as well dblwall, great shot).

[dblwall]

Thanks Matrixx that did it . Just peeled the hard liner in the fender well back and was able to get at the 2 bolts holding it on. When I get a chance gonna put all new lines on it. BTW what function does that hard plastic ball perform?

[Matrixx]

That is a vacuum storage reservoir to help assist the engine in supplying vacuum to the controls that run off vacuum. Hmm, I hope that makes sense.