94 gcl a/c still blows warm, new compressor and other parts

[lrizzo2001]

this is my last attempt at trying to fix this problem otherwise this trucks going to a junk yard. A/C compressor replaced 2 days ago after clutch seized. Liquid line replaced last week cause valve pin broke on old one. Condensor replaced last year along with accumulator. took truck to pep boys to evacuate the system and charge. Pressure holding up fine, so no leaks. liquid line would freeze while charging, but still warm air in cabin. after it took in about 24 oz of refrigerant the liquid line slowly started to get warm, and the pressure on the low side was extremely low. I can't find a good write up on removing the dash to inspect the evaporator, so I don't know the status of that. So, today I got a crazy thought, it seems to me that there must be some kind of blockage or clog right? so what do I do? I bleed out all the refrigerent, I know I know.....I said to myself, let me disconnect the liquid line, accumulator and hoses off the compressor, put an air hose to it and see if the air I shoot in comes out the other side. Bottom line, I charge up my air compressor, and spray air into the condensor, and my uv liquid comes shooting out the other end. 1 down. spray air into the accumulator, air shoots out the other side, 2 down, spray air into one of the lines going into the evaporator core, again air shoots out the hose connected to the return that I removed from the compressor. So my question is this, #1 is this a decent test of whether or not there is blockage? if it is, then what could my problem be? I reconnected all the lines again after this test, and I had 1 14 oz can of 134 laying around so I start putting it in, car drank it in 10 seconds, still not blowing cold, but not blowing warm, obviously I need to put in more, but if I don't have a leak, and there doesn't seem to be any clogs, why isn't the refrigerant circulating? At pep boys when he vacuumed and recharged the system, he told me it was showing hardly any pressure on the low side. Where does all this refrigerant go when the a/c is off?

[sreilly77]

Originally Posted by lrizzo2001

this is my last attempt at trying to fix this problem otherwise this trucks going to a junk yard. A/C compressor replaced 2 days ago after clutch seized. Liquid line replaced last week cause valve pin broke on old one. Condensor replaced last year along with accumulator. took truck to pep boys to evacuate the system and charge. Pressure holding up fine, so no leaks. liquid line would freeze while charging, but still warm air in cabin. after it took in about 24 oz of refrigerant the liquid line slowly started to get warm, and the pressure on the low side was extremely low. I can't find a good write up on removing the dash to inspect the evaporator, so I don't know the status of that. So, today I got a crazy thought, it seems to me that there must be some kind of blockage or clog right? so what do I do? I bleed out all the refrigerent, I know I know.....I said to myself, let me disconnect the liquid line, accumulator and hoses off the compressor, put an air hose to it and see if the air I shoot in comes out the other side. Bottom line, I charge up my air compressor, and spray air into the condensor, and my uv liquid comes shooting out the other end. 1 down. spray air into the accumulator, air shoots out the other side, 2 down, spray air into one of the lines going into the evaporator core, again air shoots out the hose connected to the return that I removed from the compressor. So my question is this, #1 is this a decent test of whether or not there is blockage? if it is, then what could my problem be? I reconnected all the lines again after this test, and I had 1 14 oz can of 134 laying around so I start putting it in, car drank it in 10 seconds, still not blowing cold, but not blowing warm, obviously I need to put in more, but if I don't have a leak, and there doesn't seem to be any clogs, why isn't the refrigerant circulating? At pep boys when he vacuumed and recharged the system, he told me it was showing hardly any pressure on the low side. Where does all this refrigerant go when the a/c is off?

I am having the exact same problem with my 98 Grand Cherokee. The air is not cold, not warm, but somewhat cool. And I basically did everything that you did and I STILL can't find the problem. I have another 98 Grand Cherokee that when I put the A/C on, the air gets ice cold in about 2 minutes and stays that way. They are both equally charged up, compressor runs fine. I can't figured out what is wrong. Someone did tell me that the low-pressure cycling switch might be bad and causing the evaporator to freeze up, which is why the air doesn't get very cold. I'm going to take the low-pressure switch of my other 98 Grand Cherokee with the air condition that runs great and put it on the one that isn't running great and see if there is any difference.

Believe me, this is pissing me off as much as it's pissing you off. I can't figure it out. I hope this low-pressure cycling switch solves the problem. I'll let you know.

[dksob81]

Would you be able to get an exact high and low side pressure reading?

[lrizzo2001]

doesn't that low level switch just tell the clutch to turn on and off when running the a/c less than full blast? and if that's the case I don't see how that would cause any problems. Technically you could remove that switch and just jump it with a wire. From what I've read that switch is only a problem when it's Not triggering the a/c clutch to kick in. but I could be wrong.

[lrizzo2001]

I could try, would this 45.00 manifold guage kit from advanceauto give accurate readings? and being I removed all the lines and hoses, won't I get somewhat incorrect readings since I've re-introduced air into the system?

[lrizzo2001]

High side is around 300, Low side was around 100!!!!!!, this reading was taken after re-connecting all the lines and just putting in a about 8oz of 134 that I had left in a can and No Vacuum performed, I don't have the machine for that, but I think I'm gonna go back to where I got the compressor cause I don't think it's circulating shit. I've pretty much confirmed there is no blockage, and being the compressor is the only moving part, I've gotta suspect it's that.

[lrizzo2001]

Latest update is that the compressor is working perfect. The technician feels it may be the orifice tube in the liquid line and suggested I get the whole system flushed. What's the difference between Flushing the system and having the system evacuated/vacuumed??

[dksob81]

If those are your pressure readings with the comprssor runnning you deffinately have blockage and he is right the orifice tube/liquid line is the big culprit I had this problem with mine last summer and replaced and and the a/c worked fine.

[lrizzo2001]

Do you think Flushing the system would help since it's a new liquid line? or should I just replace it?