A/C wiring questions! Something looks funky to me.

[hamiltonben32h]

Hey Everyone,

New to the forum here! Just got an 88 Mighty Max and everything runs really well. The only issue Is the A/C does not blow cold. I checked all the fuses (under the driver side dash) and tried to follow what little I could find of wiring diagrams. I ordered a Haynes manual that will be here on Thursday. I started ohming out from my a/c and something seemed off with the signal. I cut off some old electrical tape and found that the positive from my A/C is teed into another wire that goes to this small box with two vacuum lines attached. I couldn't find a part number on the part nor find anything that resembled it in the few wiring diagrams I could find. Should Any of the wires off the a/c compressor be teed into anything? also what is the weird tiny box thing with two vacuum lines? I uploaded pictures of the box and the "splice". The green circle goes to my a/c and the red circle goes to the box. Also the box looks like it's missing something??

Thanks for any/all help :)

[geezer101]

At a guess it uses vacuum to idle up the engine when the A/C is on. If that vacuum circuit is not functioning my bet is it won't idle up and/or kick the compressor on. Does the compressor clutch work when you turn the A/C on? If it kicks on then it has to be a gas charge problem. Where does that 2 pin plug connect to? And when is the tee'd connection live?

[hamiltonben32h]

So when I jump the compressor I can hear it click, but not when normally turning on the a/c. It will also idle rough when the a/c is turned on, so you might be onto something. When I get out of work I'll be able to figure out where the connector goes and when it's live.

[geezer101]

Problems is you don't know what has been done to it by PO's. Wiring is the worst to deal with after someone decides to ghetto fix a fault. They may have bypassed something to get it to 'work' rather than fix the initial issue.

[hamiltonben32h]

So I was able to follow it under the dash were it gets lost in the sea of wires and it's super uncomfortable to be under there for an extended time. I just ended up unplugging it and it didn't seem to effect anything. I drove it into town for about 30-40min and it drove the same. I will say that even with the compressor jumped the a/c still blows hot so, I'm guessing even if I managed to fix the wiring the compressor is probably faulty?

[geezer101]

Only thing you can do is try to regas it and see if it's leaking anywhere. It may not be a bad compressor, just a failed seal somewhere. You will probably be up for a new dryer but at least you can get those off ebay at pretty reasonable prices...