cold/warm/cold a/c?

[THOMAS BAKER]

My A/C will blow cold air for the first three to four minutes and then the inside of the cab will begin to get humid and the cold air acts like it mixes with the hot air. For the next three to four minutes the air temperature is warm and then it returns to cold. This cycle will repeat itself over and over. When the air is blowing warm the low side has extremely high pressure. When the air is blowing cold the low side is with in the normal pressure reading. I thought I would check the blend actuator behind the glove box. It engages as I turn the a/c switch on. When the air temp warms up the actuator stays engaged (no voltage drop and no visual change). Any suggestions?

2002 7.3 Powerstroke - stock – 81k miles.

Thanks, Thomas

[THOMAS BAKER]

Okay, I think that it is the ac clutch. Does any body have any advise on how I can test the clutch? Can I replace just the clutch? I have several people tell me I need to replace the compressor. Any ideas would sure be appreciated. Thanks.

[duckslayer74]

Have it checked to see if it is fully charged. It's prolly a little low on the 134.

[jc82chevyman]

You can replace the clutch and the only way to check them is check the continuity of the coil and if it is getting powere its nothing more that an elctromagnet. But it sounds as if your compressor is bad, it could be a faulty clutch. When it blows warm pop the hood and see if the clutch is in fact turning.

[THOMAS BAKER]

The a/c is fully charged. I do not have continuity at the coil. I do have power to the switch. The clutch does not engage, and now the air temp is warm most all of the time.

[jc82chevyman]

If you have power and the clutch shows OL then you have an open in your field windings and you need a new clutch

[Eric]

I was having the exact same problem as you. I took the glovebox down and started looking at everthing. I smacked around on all the parts and it's been working perfectly for 3 weeks now

[THOMAS BAKER]

Originally Posted by whitelongbed

I was having the exact same problem as you. I took the glovebox down and started looking at everthing. I smacked around on all the parts and it's been working perfectly for 3 weeks now

Too funny, but true. All you need is a hammer and duct tape. If it doesn’t move and it is supposed to a hammer will fix it. If it moves and it’s not supposed to duct tape will fix it.
I will Smack around behind the glove box first and then replace the clutch. Thanks for the info.

[no-tel-in]

mine was doing that and it was the clutch, i know someone who had too much 134 in it and it did just about the same thing, so check the freon either low or high

[elevatorguy111]

Darnit! It is the clutch. I stripped some of the insulation to connect a meter. the ac worked great for 5-10 min straight, (I thought it wasn't going to do it). The meter read 12.9VDC to 13.1VDC. I switched the ac off then back on. The meter read 0v in off and right back to 12.9vdc when switched back on. Warm air started blowing this time and the clutch was not turning!