Problem: A/C blows warm to hot air, so no cold air when any of my controls are set to AC or Max AC and temp turned down (to blue obviously)....heat works great.

A/C started intermittently working last summer, worked great when I was running 70 mph, but in stop and go traffic it would start to blow warmer/hot and also developed the problem of not wanting to shift immediately from changing the airflow settings from defrost to dash vent etc., it would change airflow when IT felt like it. My first fix was to add coolant to the system which I did and noticed no noticeable change.

After, researching the site, I am going with the whole air gap problem on the A/C clutch because it seems like a reasonable start point and not as costly and easy for me with my limited mechanic skills. So going with the this train of thought I attempted the air gap fix last night.

Step 1 in the air gap fix was to turn the ingnition to on and the way I understand it this should engage the AC clutch (draws the air gap closed) in order to loosen the 8mm bolt to get to the shims. This did not happen and the bolt and the plate would only spin so I was back to square 1 in about 2 minutes.

My thought now is maybe an electrical issue seeing as how the clutch is not engaging even when the key is turned on....any thoughts?

Any thoughts/suggestions and criticism is greatly appreciated!

 

If the system pressure is to low the clutch will not engage to protect the compressor. You need to put a set of gauges on the system. If you don't know what your doing you can do more damage than good to an ac system. You can jumper the low press. cutout switch to see if it's a low press. problem.
but once again you need to know what your doing.

 

69cj...
Thanks for the input....I know with my limited abilities and knowledge that I can potentially make a problem worse. How hard and would you be willing to explain jumping the low pressure cutout switch so I can potentially isolate that problem? Thanks.

 

Low press. sw. is on the dryer ***. It's a cylindrical device on the passenger side firewall. Unplug the sw. on the side of the cylinder and put a jumper wire inside the plug. When you start the engine the clutch should now pull in if low charge was the problem.

 

Mine would blow warm also , then found a thread on here that told me to check the grey vacuum hose on the passenger side heater valve, sure enough it was off, check to ensure your vacuum lines are connected while you are at it

 

Raptor131,
Funny you should mention gray vacumn hose. I rebuilt my a/c system(new condensor, compressor, dryer, orfice tube, evaporator) last year. Last part back together was the gray hose, could not find where it went, still do not know where it goes. Plugged it and the a/c works great.
This seems to be a classic leak case, filled last year, now low.
IT WOULD BE BEST TO HAVE A KNOWLEDGABLE person check the a/c system out. Freon w/dye may help you find the leak.

 

On an 04 extended cab, the grey hose just gets plugged. There is actually a plastic dummy nipple molded into the heater box to accommodate it.

On 99-04 trucks with Crew Cabs, and Excursions, the hose goes to a valve that shuts coolant flow off to the heater core when the control **** is OFF and in the MAX A/C positions. Extended cabs, and Regular cabs do not have this valve.

All 05 and up trucks and Excursions have it.

 

I outta rep you on this one. I have had it plugged for 1 yr because I did not know where it went. Thanks dc, God Bless
Eagleinms

 

JTAC, the OP, stated that his clutch was not engaging. That would not be the grey vacum line.

 

Any word on what the issue was? I am having the same problem on my 04 6.0 Crew cab. The heads were done in December and now I have no A/C when I need it. I keep hearing many different pressures the a/c is supposed to be when charging it. Does anyone know the actual pressure for when I check tonight? I also cant seem to find a Grey hose anywhere on the passenger side firewall.

 

the pressure is going to be determined by ambient temperature. See what the static pressure is ac off and truck off and go from there. Sounds like you are gonna be low on freon.