Bought a weekend driver red '83 944 early this summer. A/c did not work . Previous owner drove it about 3,500 miles in the past 6 years and never used a/c. I checked fuses and never a peep. Today, I am making a quick run to store with sunroof out and all the sudden I hear this big wind. Look up at trees but they not moving . Then I realize the ac fan is running full blast. Huh???? Turn it on and off numerous times and all is well, compressor clicks on and off, all 3 speeds work, and slightly Coolish air comes out. It is in the driveway now and I'm going to add some freon. ANY ideas why it decided to work all the sudden???? Should I do anything to make sure it continues to work?
Only 2 things that have changed are its sat for 2 weeks while I was out of town, and the weather has been coolest since I've owned the car. To my mind neither if these could have caused the a/c to work.

 

Welcome Patrick,
You have an '83 944 with an early AC system like my 924S.

1. A corroded ground has temporarily connected.
2. The fan relay contacts have temporarily connected---Does your blower fan switch actually turn on the fans?
If not, there is a fathom ground ---very difficult to trace has finally connected.

Now, If the car has been converted to R134a only use 2 cans max. If it has been converted go to Wal-Mart and get a can of R134a leak sealer and use it first to seal the "O" rings---then add "1" can of R134a at first and see what the temps are.

If The car has not been converted, just adding a couple of cans of R12 may be an expensive temporary fix.

GL
J_AZ

 

Thanks for reply. Ac fan switch turns compressor on and works correctly on all 3 speeds. The heater fan controller has always worked.
How do I tell if it uses r12 or r134?

 

There should be a "Conversion" tag or sticker. If not look for large "High-Low" connectors used on R134a. These are press on hose connectors.

R-12 uses small "High-Low" hose connections that screw on.

You cannot mix Freon. R134a costs about $6-10 a can. R12 costs about $80 to $100 a pound retail at AC shops to recharge, or $35 +- on Craigslist for 12 OZ DIY.

Search is your friend.

J_AZ

 

The AC relay can get burned contacts, in one of mine the contact pads were misaligned from the factory. I had to clean and straighten them. The misalignment caused them to have a much smaller contact patch than expected and they burned.

 

If you go to Wally world and get the sealer..a word of caution about this. You can get refrigerant with a leak sealer already in it...this works good on the o-rings. However, If you buy the Super Seal product, be absolutely certain that after you put it in, that you run a can of freon (refrigerant) through it right after. The sealant sets up on contact with air. You must do this to keep the schraeder valves from gluing themselves shut. When you go to add the refrigerant, be sure the engine is running, and the A/C is on high speed. It would be best, to have the system evacuated, leak tested and recharged, considering the age of the refrigerant, that way you KNOW what is in the system. Get it converted over to R134 A if it hasn't been done yet. All the refrigerant must go through the SUCTION ( low side) port of the compressor. Do not invert the can as the liquid in the can will "slug" the compressor and possibly ruin the valves and other innards in the compressor. Hope this helps some. Contact "Griffiths" here on R-List if you want the straight poop. Thanks

 

Thanks all for the replies. I guess it's about I met my local Porsche shop, touring cars inc.