Question on A/c bot blowing out of center vents
 

Finally got my a/c charged and i have a problem. My a/c blows hard out of the defroster vent and i have warm air dumping onto the passenger floor somewhere. I didnt dump on the passenger floor before the a/c started working. I removed most of the dash to check everything out and everything looks normal. All the plastic pathways are in tack.

The owner before me im positive remove most of the dash to install an aftermarket stereo and messed with the a/c at some point.

Is there a way to force the bellows to only blow out of the center vents?

Any ideas? sorry for the long post

thanks in advance.

Vacuum switch
 

Try moving the vacuum slider switch, it is directly below the steering wheel on the panel that is directly below, when it it in the wrong position it kills the AC.

Yeah, what he said. The long answer is your dampers are sluggish or locked in current position. They work via a vacuum system - and we can deal with that if you can't get them to work right enough now to make you happy - so you can skip a bit of repair/replace work...:redface:

The spot on the panel under my steering wheel where the vacuum slider switch would be is completely smooth like there never was a switch there. Im guessing mine is controlled all electronically. Unless they moved the switch somewhere else.

How can we get this to work. It is way to hot in florida with an a/c that hardly functions ahha

any help is appreciated

Your air coming out the defroster is the Z31 default position when the dashboard control switches aren't working. They don't work when your vacuum hoses are bad/broken/missing and/or your vacuum power is weaker than it needs to be. No quick solution but checking every vacuum hose and replacing the bad ones. If they're original, they need replacing anyway.

Check out thumper's write up at Vacuum Lines and get the right inside diameter hoses at a good parts store. Replace them one at a time so you don't mess up. Hoses under the dash are hard to get to - but they must be done. That's probably where your failed hoses are...:wink:

Here is everything you need to know about the vacuum system of the Z31.

88hybrid.com • View topic - V acuum System: Replacing Vacuum lines

88hybrid.com • View topic - Vacuum System Under the Dash

88hybrid.com • View topic - Vacuum System: Fix for the Vacuum Pump Always Running

XenonZcar.com Z31 A/C Problems

http://www.atlanticz.ca/zclub/techtips/vacuum/

Tom's z31 300ZX Page

thumper300zx.com - Nissan 300ZX, Z31, Z32, S30

Robo