My A/C fires up fine....great A/C at about 45 Lb....Suction tube nice and cold ...high side from condenser nice and hot......but then while driving all of a sudden...musty warm air starts comming out... then after a while the A/C comes back.....Started truck at home ran A/C with gauge for about 15 Min did not cut out but It will when I drive around this morning....been doing It off and on for about a week...any thoughts?...

 

That's funny. I was just about make this same post. My regular A/C works for roughly 5-10 minutes and then starts blowing plain air. I then switch it to Max A/C and it takes about 2-3 minutes for that to start working which eventually stops blowing cold air after a little while also. Does our systems just need to be charged or something?

 

When it happens pull over and lift the hood and see if the compressor is cutting in and out!
Could be low refridgerant or a defective pressure sw.
Also a vacum leak to the blend door actuator.
What yr truck also?

Rich

 

There is a TSB on a/c systems. They will replace the seal on the compressor if you have a certain brand compressor. I dont know if that's your problem, but just a heads-up!

 

My truck is the 2004 PSD CC. Does that make a difference?

 

TSB Main Page

TSB
06-4-9 A/C COMPRESSOR NOT OPERATIONAL / LOW FREON - SHAFT SEAL LEAKS

Publication Date: February 21, 2006

FORD: 2003 Escort
2003-2006 Focus, Mustang, Taurus
2003 Explorer Sport, Windstar
2003-2005 Excursion, Explorer Sport Trac
2003-2006 Escape, F-150, F-Super Duty, Ranger
2004-2006 Freestar
2006 Low Cab Forward
LINCOLN: 2002 Blackwood
2006 Mark LT
MERCURY: 2003-2005 Sable
2004-2006 Monterey
2005-2006 Mariner



ISSUE:
Some 2002-2006 vehicles equipped with an FS-10 A/C compressor may experience a non operational A/C compressor due to a low freon level caused by a leaking shaft seal.

ACTION:
Replace the A/C compressor shaft seal following the Service Procedure.

 

It depends on the environment in some places. I don't know about Virginia, but in Texas for example we have been in a drought for some time now. Like Rich (FortyFords) stated, look at the compressor - sand/grit gets trapped in the clutch and widens the gap.

DO NOT ATTEMPT IF NOT FAMILIAR: An AC tech can take a tool and tap the clutch on the compressor to see if it catches. If so it is either a weak switch or the gap is too wide to for it to engage.

 

Sorry Rich, Its a 2001 F-350 Super Duty......I added a little 134a yesterday....as usual Its Ice cold when I first start the truck but sixty mi later Its still fadeing In and out........I will try to jump under the hood while Its doing It and what If the compressor IS cutting In and out ??? what does that mean And how do I fix It......

 

check for vacuum issues

 

Vacuum In general or within the a/c system????? and If you do mean a general vacuum leak how does that effect the a/c???also any tips on locating the leak or problem..??? Thanks, Dick

 

He means a vacuum leak that would keep the vacuum operated A/C & Vent doors from oerating properly (The doors are operated by vacuum). If your A/C is cold and you get warm/ non A/c'd air, a vacuum leak may be to blame. I had a Dakota that would blow hot air when going up hill under load. As soon as the terrain leveled or went down, cold air came back. They diagnosed it as a vacuum leak (Almost 8 Years ago, so I can't recall all of the details).

 

thank you....

 

The problem is compressor clutch air gap. Use a .016 feeler gage and see if it is very loose between the clutch and pulley. If it is, remove the clutch disc. Inspect both clutch disc and pulley faces, if they are is reasonably good shape, install and smaller shim and call it a day. If they are chewed up, replace both the pulley and clutch disc.

It is not low refrigerant or a vacuum problem.

Let us know how you do.

 

My compressor has a gap of .028. I pulled the clutch but did not see a shim. Where exactly would it be located?
Thanks guys,
Doug

 

It looks like a washer. Different thickness washers gives you the adjustable air gap.