I have not had the chance to get a gauge reading yet, but I probably will this weekend. The problem is that the AC never cycles off though, not even at night when the temperatures are down to the 80's. I could understand that theory during the day when its 105 outside. It has been one hot summer here in Texas, but at night it cools off pretty good and it should cycle at that point but it doesn't.

 

I have not had the chance to get a gauge reading yet, but I probably will this weekend. The problem is that the AC never cycles off though, not even at night when the temperatures are down to the 80's. I could understand that theory during the day when its 105 outside. It has been one hot summer here in Texas, but at night it cools off pretty good and it should cycle at that point but it doesn't.

 

I bet it's a high side solenoid!
It makes sense, however I have been in some REALLY hot weather and have NEVER seen the issue. So if it is "then it is" I just have my own opinion on this and I agree to dissagree with you agreeably. Also I talked about the differences in home and auto A/C.

 

Wait until the night when its cooler, turn ur air on full blast for about 10 minutes and let the system get cold then turn your ac on its lowest blowing setting and if your compressor doesn't cycle then you have a problem.

 

And i have to agree it has definitely been hot in Texas this year. I redone my wifes system and im pretty pleased with it. Sitting at idle it blows about 48-50 moving or reved it blows 38-40 regarless if its 108 or not.

 

Ok So this morning it was cycling correctly. Until the engine got to operating temperature than it stopped. Once the engine hit between 190 and 200 the compressor just kept running. It was only like 89 degrees outside. So I realized I have a coolant leak and filled it up with water, the engine temperature went down to 190 but the compressor still wouldn't cycle. After I drove around the block and got it to about 185 it was cycling again the engine went back up to 190 and it stopped cycling again and continued to make my truck temp rise to 205. Any suggestions? I don't understand why my engine will run normal with the AC off, I turn the AC on and it cycles properly, the engine heats up at idle and the AC stops cycling. I am guessing that I am still having an engine cooling problem but I don't know what, yeah it had a leak but I filled it up completely. I have already replaced all of the cooling components associated. Now I will find the leak but it still doesn't make sense. What temperature is the engine supposed to be at for the compressor to continue to cycle? Normal running temperature is 192 so why would that make it continuesly run?

 

Is the a/c not cooling when it does this? 192 is the factory t-stat that comes in most of them.

 

190 is the normal stat, but 2degrees shouldnt make much difference

 

Still sounds like your low on freon. Wrap the low side lines with foam and see if it stops, this will help ya drop about 10 degrees on the a/c if anything and the foam is really cheap!

You need to take a pressure test on hi and low ports.

 

Alright, so today, I evacuated the system and replaced a couple of the bolts in the expansion valve. (Lost them on original swap, and got some used ones at the salvage yard) I figured out that there was a leak there, due to makeshift bolts that I had used originally as replacements.

So no more leak. I currently have 200 on the high side and 45 on the low about 91 degrees outside maybe 95 was the high. AC is blowing cold, but the compressor still does not cycle off and the truck still starts to run hot if it idles too long. Talked to a guy at Firestone and he said that if its an idle only problem that it has to be airflow, (Considering I have replaced everything else) but the damn fan clutch is brand new too. It's a thermal fan clutch installed in June. I don't get it. I read somewhere else that exhaust back pressure can cause this problem too, does anyone else here know if that is true? I am pretty sure that the AC not cycling is adding to the problem, and maybe I am having an airflow problem, but do companies like 4seasons typically sell bad fan clutches off the assembly line?

So the question is....What next to test in the AC system to make sure that the compressor cycles and can a plugged exhaust system cause this too? (BTW I found out I had a coolant leak too, it was the bypass hose had a hole in the side of it but I fixed that so no more leaks anywhere, AC or coolant)

Thanks!!

John