Dumb A/C question

[Army_F_body]

Okay I posted a long time ago about the badger sound coming from my dash when I hit the A/C and cranked it up. Finally got some time to pull and replace the heater/ac blower motor.

The problem now is when I turn on the AC and crank it up the air blows from the defrost vents on the dash top, but not from the vents, right away anyway. After crusing for about 5-10 minutes and the car heats to about 160 degress the vents kick in and it's winter in the summer time.

What confused me today is when I hop in and turn on the ac at ignition it's blowing like winter in the summer, etc. I stop at the local Cirle K for a frosty beverage, get back in and nothing right away. Kicks in a way down the road like normal.

The question I have is how do I get the vents to work as soon as I turn the ac on? Am I about to run out of refrigerant? If so do I need to buy a retrofit kit, or did the 92 models already have the 134A refridgerant?

Never thought the ac could be so complicated :(

Thanks, y'all [img]smile.gif[/img]

[ August 21, 2003: Message edited by: Army_F_body ]</p>

[Jerriko]

When the air blows out of the defroster slots, is it still cold? If so, I think you have a vacuum leak. The slider that directs the air to defrost, vents, heater, etc is vacuum controlled and if there is a leak, the default setting will be on (defrost) instead of the desired setting. The usual place the vacuum leak occurs is right on the back of the climate control unit. The is a cylinder with 4 or 5 vacuum lines going to it. There is a seal on the inside of the cylinder that is the culprit (or sometimes a peg on the inside of the cylinder that keeps pressure on the seal may break). Main question is that do you hear a hissing sound?
Jim

[Army_F_body]

The air out of the defroster vents is cold, cold as when it's blowing out of every vent when it works.

I notice a hissing sound coming from the silver cylinder with all the lines running into it next to the blower motor housing, passenger side of the engine. Is this the cylinder you mean? The hiss last for a few seconds after I shut everything down.

Thanks for you help!

Rob

[Jerriko]

That wasn't the cylinder I was referring to but regardless. The cylinder I mean is attached to the back of the climate control console just above the radio. The hissing sound could be the source of the vacuum leak, but I am don't think so. The silver cylinder, the evaporator, doesn't have any vacuum lines running to it, just metal hoses flowing the freon through the condensor and ac pump. The vacuum leak I am describing would usually be inside the passenger compartment under the dash. There is one major rubber line (not large in diameter) that travels from the engine through the firewall to the back of the climate control console which supplies the system with its vacuum. If that line or any other one in the system has a cut or bad connection, this will cause your vacuum leak. Try this, try the heater on high and notice where the air is blown from (ie defrost, vents, floor). If it blowns out of the defrost, its a control problem (vacuum) and not an AC problem.
Jim

[Army_F_body]

Yup, the heat blows from the defroster vents. I've been told that I would have to remove the whole dash to get to the vacuum lines. Is this true or can I get to it by removing the passenger side under dash panel?

Thanks,

Rob

[Jerriko]

First thing I would do is remove the radio bezel panel and pull out the climate control center. Once you do that, you will see a cylinder with a ton of vacuum lines attached to it. With the control center removed from the bezel, operate the heater and AC and listen for hissing. Jiggle the hoses around to see if there is a bad connection/ cut present. If you don't find your problem there, removal of the entire dash maybe necessary to find the leak. But before you pull anything apart, look under the hood again. You mentioned that you heard a hissing sound coming from the evaporator/ blower area. Look for any vacuum lines there. That hissing sound in that area bothers me. I don't remember a hissing sound normally coming from there.
Jim

[Army_F_body]

The hissing comes from the metal line running from the condensor to the evaporator.

I find resistance from the climate control panel. Is there anything I need to disconnect? I recently installed a new CD head unit maybe it's pinching something. Anyway next week I'll have some time to play with the car again.

Thanks,

Rob

[Jerriko]

Installing that new stereo may have caused the problem. Once you unscrew the climate control, it should slide freely out. If the vacuum lines are pinched behind the radio, it could have also loosened the connection causing a vacuum leak.
Jim

[Army_F_body]

Success. Pulled out the stereo and climate and controll module to find the elusive cylinder and vacuum lines. The vacuum lines were bunched up and pinched, so I fiddled with them and moved 'em back enough to not get pinched up again.

Needless to say air works and all is well!

I appreciate all your help on this Jerriko :D

[Jerriko]

Glad to help.
Jim

[91CamaroRS]

I have a similar hissing situation, except I notice mine when I turn the car off and when I turn it back on. The hissing goes away after it's turned off, but when I turn it back on the hissing persists until I move the selecter to something air conditioning then back to off. Any ideas, or does this sound like the same problem as described above?