82Porsche928

I have no clue where to start here. My ac does not work (wire is unplugged, but nowhere to plug it in)
When heat or air is turned on in any position on the slider, air blows out of defrost. I can adjust the power with the ****. I get a "wheeze" out of the door vents.
Hot air is constantly draping out of all vents as well. I have read this can be caused by the small pump under the air cleaner, which I have purchased, and will replace. Any input is appreciated. I will be slowly working on this project. Hopefully won't need to remove console dash and pod again...

michael j wright

I would first of all do a search for WalleyP and his write up on HVAC systems before you do anything. Also would be helpfull if we knew what wire was unpluged, these car's have quite a few for the ac system.

HaydenM1974

Sounds like you may have vacuum leaks...Is the recirculation flap above the fuse panel opening up? It sounds like your heater valve may be letting hot coolant circulate through the heater core. Until my blower motor just took a **** I had fairly cool air coming through the vents. I can tell you what I did in my system but I would treat it more as a troubleshooting step and only do it if you are planning on switching to 134.

Randy V

That's not a 'pump', it's the hot water valve that controls hot coolant entering the heater core.

Being you are in Las Vegas, I imagine you will be feeling hot air regardless of whether that valve is closing or not.

82Porsche928

I'm getting 80+ even when it's in the 40s out once the car is fully warmed. I will post part number tonight

Alan

The default posistion of the air distribution flaps when the system is off and when vacuum is not present are for defrost vents to be open, and for the hot water valve to be on.

You may have electrical or vacuum (or both) issues - but sounds like your vents/valve aren't doing anything. Vacuum is easy to test (with a mityvac - get one, you'll get to use it more than once).

With the water valve open you have a fully heated heater core, the comb flap also defaults to open so all air though the evaporator gets routed to the heater box depening on the mixing flaps it may go around the box or through it (or some of each). In any case it will pick up heat.

Take the cowl off the area between the firewall & bulkhead - locate the evaporator feed tubes to the expansion valve - any cold when running in AC mode? Likely not I'm guessing...

Alan

82Porsche928

I will have to order a mighty vacation tonight

Alan

Yep get one of those too -

HF has some generic branded versions - usually work OK - anyway the original is <$50. Much cheaper than any vacation!

Alan

syoo8

Read this thread several times. Dwayne outlines what you need to test.

Defrost defaults to 'open' in the absence of vacuum, while the others default to closed.

In the absence of vacuum, the heater valve stays open, which means you have hot air all the time.

You most likely have HVAC actuators that have little tears in them. Almost all of the cars have them. My car also had bad solenoids.

James Bailey

Dwayne does such great write ups !!!

82Porsche928

Have to love auto correct!

The Forgotten On

Pep boys carries a actual might vac in their own packaging. It's cheaper too with the same stuff.

82Porsche928

Thank you! I will get on this later this week. Hopefully I can get a few of the guys here to help out!

82Porsche928

So I have a brand new heater valve, in my parts drawer. This is what I was told could be letting hot air into the car..

The Forgotten On

They do, just be sure it's not the made in China one from a few years back as those split and spray coolant all over your engine.

Also be sure that there is vacuum getting to the calve in order for it to close, this is where the mighty vac comes to play.