I posted here about 3 weeks or so ago about an overheating AC. I wanted to update what I have since installed and encountered.

I installed a HD radiator/2 row, flushed the system, installed a brand new water pump, installed new heater hoses from pump and block to firewall, and installed a new fan shroud, courtesy of FORD. I also moved my engine oil cooler from the input side of the radiator to the adjacent side (passenger side) to reduce heat stress on radiator.

Now I have recently noticed and it may be getting worst an air leak or vaccum leak coming from the front of the dash in the vent/ac control selector ****. I can hear the hiss change as I select different settings and it always constantly "hisses" even when I haven't used the ****,( i.e, sitting for 1,4,6,8 or so more hours, etc.)

Also, if I have been using the AC I can hear this chissing, hissing sound coming somewhere from near the front of the passenger side in the engine compartment near or in the area of the Condenser when I shut the engine off. I believe this to be normal, but whenever I go to Norm A/C, the temp gauge really goes from "R" in normal range, to the Low side of "A" of normal, and this sticks from anywhere from idling to sometime being on the highway at cruising speed, and then it will drop to the High side of the "M".

It seems to me that even sometimes the condenser coil needs to flushed sometimes but I'm just an 'ol country boy. The dealership said that everything checked fine, so what are anyone's thoughts.

I appreciate everyone's help and I look forward to any ideas and suggestions.

 

Check to see if the vacuum harness is 100% plugged in. Try to follow the leajk if not at the controls.
If its the Mode selector switch, Its a Motorcraft part and not overly expensive to buy.
You MIGHT be able to disassemble the old one, and regrease it.

 

Well, I got around finally to pulling the AC control's out and found the problem in the switch.
Ford Part #F2DH-19D961-AB
Motorcraft Part #YH530

Max air selector had air blowing back through it, only one that was donig it when I tested the plugs. I got the new part since someone had ordered one and never picked it up, and then installed it. Then I did some vaccum tests and realized the "dreaded brittle and dry-rotten vaccum tube (the white one)" I did some "riggin" and got some new tube, new nylon flanges, and some heat-shrink tubing and WOW! All I can say is that my MAX air freezes me out!!!! Never kicked out once while I was getting high RPM's on the roads an the hills.

 

I also meant to ask, that whenever I use the AC/defrost and other AC/and MAX AC, that I hear my compressor going "squeak, squeak, squeak" in a interval, about every 1-2 seconds..Is that a major repair I hear, or just a something else I cannot pinpoint?