ok this is unique, as far as ive heard, its very strange problem so I havnt bothered searching for it on the forum, sorry if its common

okay, if AC is on, works fine, air blows out, however, if i press on the gas to accelerate, the air shuts off and comes out the window vents at a minimal speed. I tried looking to see if it was dependant on the RPM but it wasnt, it just seems if im Decelerating or idle it works fine, but if i Accel, it basically shuts off.
(ex: i could be cuising highway at 65mpg at 2100rpm...its off, but if i let off the gas, it switches back to the main front vents and blows fine.)

the only other info that might be helfpul is:
a) this started around after i went to pismo for the first time. (beats up the car a little, bottom out a few times)
b) the air box (black plastic containers) toward back left (assume looking under hood) are brittle, cracked, and has a few holes near the compresser input pipe

any ideas?

 

Are you sure it's coming out of the window vents? The HVAC actuators are powered by manifold vacuum Sounds like you are having a low vacuum problem that is causing the actuators to return to their unpowered position, which typically is the floor vents...

I'd make sure that all of the vacuum lines are connected on the engine as well as the line that leads into the HVAC system and that there are no breaks or cracks in the lines.

 

im almost absolutly positive, the air comes out the dash (defrost)

 

Geez, sorry, yeah, defrost is the default location... I don't know what I was thinking. For some reason I was thinking by window you meant side window... But I still shouldn't have said the floor...

So this definitely sounds like you have a vacuum supply problem to the HVAC control panel.

 

so is this something easy to fix? or actually, where can i find pictures or something to tell me how to fix this

 

Not really going to find pictures showing you how to check your vacuum lines. For suspected underhood vacuum leaks, I use an unlit propane torch and just follow along all of the lines with the engine running. If the idle increases (due to the burning of the ingested propane in the engine), you found a leak. Don't stop there however, continue on until you have done all of the vacuum lines. On a '95, its quite possible that there are many lines degraded to the point of needing replacement.

I can try to hunt you down a vacuum diagram this weekend, but I don't have access to many of my resources while I'm at work.

 

Definitely a leak in a vacumn line. May need to pop the dash trim and look on the heater control, be sure you check that black plastic ball that hangs on the hood also (can't remember what it's called).

 

Take your vac gage and check the Grey line on the vac harrness on the back of your HVAC contol on the dash. If you have good engine vac there then the problem should reside between the hvac control distro and the vac accuator that controls the actual vent under the dash.

I am at this point. My vents only work from the defroster and the floor vent to a lesser degree.

If you happen to find a solution, readable diagram of which under dash actuator controls what...I would be happy if you passed it on.

Thanks

 

I would check the vacuum resivoir, and also I believe there should be a check valve that only allows vacuum flow one way, that way when the engine is at full throttle and has no vacuum it does not give the vacuum that is holding the blend door in the vent position, to the engine.