A/C cooling problem

[csamuels]

A/C question.while driving my 2002 sport trac my A/C will sometimes act up. The A/C will be in the normal mode with the fan on high cooling fine and all of the sudden the air will change (you can actually feel the difference in humidity) and the A/C will stop cooling. I can turn the switch to the off mode for a couple of minutes and then back to the A/C mode and the system will work fine again. As a matter of fact I have done this on a road trip and it didnt act up again for hours.

I have pulled down the system and it holds a vacumn. We have recharged the system but it didnt cure the problem.

I own a body shop and we can handle the normal evac & recharge but this one can of has us

The high side pressure was a little high during recharge.(restriction somewhere??? If so where???)

Also I have had it stop cooling when I have gone from normal interstate crusing speed to a slower speed to exit the interstate.

So.suggestions???????

 

[EddieS'04]

maybe theblend door is acting up. See link

 

[Larry Hampton]

That's my guess too, I never turn the heat into the red after I read this.



By my A/C thermometer, my air comes out at anywhere from 38-30 degrees on recirc. :banana:

 

[scott degroot]

SOunds to me like the system is freezing up. This can be caused by a few different things. A faulty low side pressure switch that won't let the compressor cycle properly, an overcharged system where the compressor can't pull down the low side enough to trip the low side switch, a plugged evap drain. I'm curious as to what your pressures actually are

 

[csamuels]

L1Tech..agree with you. We will hook up the system again this week and Ill post the readings.

My only follow up question is: could there be restriction in the system?

The trac has 258K miles so I just to try and make sure Im not missing something.

I had to put in a new thermostat housing this spring and at that time cleaned off the condenser from road debris as well as the radiator.

Any common accumulator/receiver-dryer issues occurring????

 

[scott degroot]

Lets see what the pressure readings are first before we go looking for a restriction. Get readings at idle and also at about 1500-2000 rpm's