Hi all, i’m looking for some guidance on troubleshooting my AC problem.
It’s currently blowing hot air. I took it in to a shop and they checked for leaks and didn’t find any. So they filled the coolant back up with a dye and checked again, still nothing.
They hooked up the pressure monitors and said that the low end was 80 and the high end was 150 and their determination was that I needed an new air compressor.

I decided to do the work myself, so I had a mobile AC guy come to drain the coolant. When I told him what was going on he said it didn’t sound like a compressor issue, but was probably the expansion valve.
He hooked up the pressure system again and verified the same numbers as the shop (80lbs on the low side, 150 on the high). He fully thought this was an expansion valve issue.

With that in mind I replaced the expansion valve, and the dryer for good measure. Then he checked for leaks (there are none) and refilled the coolant. But we have the same issue.

He checked around and we found that one of my fans is not coming on.
He is going to check with someone else to confirm his thoughts, but he still believes it is not the compressor, and it may have something to do with the fan not coming on.

Any help is extremely appreciated. I live in California….no AC is no fun at all
Mark,

I do not see improved cooling when driving at excessive speeds, at least nothing really noticeable. Because it’s hot I drove with my windows down, and there was a slight breeze every now and again, so any cool breeze I felt was attributed to that. But feeling the air with my hands I felt no difference.

I will see if I can try the hose trick to confirm that it is in deed no an issue with the fan.

I ran the AC full blast for about 45 minutes yesterday on my way home. Both with circulating air (which blows significantly harder out of the vents) and with flow from outside. There was no change, the A/C is still blowing hot as ever.

With regard to the possible blockage in the evaporator, before the AC coolant was filled again, it was hooked up to a vacuum for about 15-20 minutes to suck out any moisture (so I am told). Would that not have fixed any blockage in there?

I will talk to the tech again to see if we can record the pressures. I don’t have the equipment to do it myself. I
Motorhead,

Maybe I am missing something, but there isn’t any electricity to the expansion valve. The only connections to the expansion valve are the two coolant hoses that go into the front, and the two connections that are on the firewall. Nothing electricity related that I am aware of.

J.R.
The AC guy checked all the fuses when he was trying to find out what was wrong with the fan. He determined that power was getting to the fan, but the fan wouldn’t come on. I have ran the AC and drove the car to get it quite hot and still no fan.

Of course I didn’t check this myself, so I will do that today. Thank you for the link. I really hope this helps. :(

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