AC troubleshooting

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PG01

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so it holds vacuum and no leaks, compressor kicked on but no cold air correct? gotta be inside then.... unless i missed something... blend door, controls. you have rear a/c?
 
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Dantheman1540

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so it holds vacuum and no leaks, compressor kicked on but no cold air correct? gotta be inside then.... unless i missed something... blend door, controls. you have rear a/c?


Yes It will be replaced since it's out and it's super easy to get to it's in the line between the high and low port. It had a little something on it but I could clearly see through it. Don't think it would cause nearly 500psi buildup.

Yes you are correct compressor is on front and rear is set to coldest setting and highest blower speed but completely warm air.

I think something was causing a pressure buildup which is why the service port began to leak and the air got warm while driving. Just not sure what would cause that. Maybe the compressor took and dump? Although it's coming on fine and sounds normal no weird noises.
 

PG01

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i just reread your post you said dye was coming out of valve, maybe there’s dye and stop leak stuff gumming up the condenser??? in turn giving high high side readings??
just throwing ideas out
 
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Dantheman1540

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i just reread your post you said dye was coming out of valve, maybe there’s dye and stop leak stuff gumming up the condenser??? in turn giving high high side readings??
just throwing ideas out


Yes dye was coming out I assume someone worked on the AC system before or added a can of "AC pro" or whatever to try to get it cooler on a hot Texas day. It's very likely that could be gumming something up but strange that it would just suddenly clog it completely.

Might be worth it to reach out to @UmmScott . He’s pretty knowledgeable in the HVAC systems in these vehicles.

Send um in! I'll take any help I can get. Contemplating taking it to work tomorrow and finding a place to drop it off or taking the Taco and doing more research.
 

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Hopefully you pulled a vacuum and didn't leave that cap off! [emoji16][emoji16]

Forgive me if i missed something. You have front and rear ac yes?

You're pressures are Way Too Low especially at startup.
Even on a nice hot day with the front AND rear system on your low side will start up around 70 quickly pulling down to 50. And your high side will be higher around 250 and come down from there.

Are you getting the full weigh in charge in there? Those cans suck and aren't that accurate but should work if you get the right amount.
Btw 2 small cans is not enough for a front and rear system. I dont think you're adding enough especially with those pressures.

Another thing to help is to check superheat. Pretty easy on the front system. (Superheat is an indicator for how much liquid is in the evaporator and tells you how much work/change of state the evaporator is doing.)

Measure the line temperature right after the orifice going into the evap and measure outlet temp of the evap.
Subtract the inlet FROM the outlet. That is your superheat. If its really really high like 50F or even 30F, then you dont have enough refrigerant feed to the evap: ie low charge, restricted orifice. Superheat on a car should be anywhere from 0 to 20 once its cooled down.

Also (again sorry if i missed this) if you have rear AC. If the rear AC works pretty good but the front sucks or is warmer, you're low on charge. Rear system uses an expansion valve. Exp valves adjust and regulate themselves. The front orifice doesnt. So when system is low the rear will hog all the liquid available.

Hope this helps. Hit me up if u need more input man [emoji106][emoji106]
9cbc17f7763c5b009f75f2b060abb2d7.jpg


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Dantheman1540

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Hopefully you pulled a vacuum and didn't leave that cap off! [emoji16][emoji16]

Forgive me if i missed something. You have front and rear ac yes?

You're pressures are Way Too Low especially at startup.
Even on a nice hot day with the front AND rear system on your low side will start up around 70 quickly pulling down to 50. And your high side will be higher around 250 and come down from there.

Are you getting the full weigh in charge in there? Those cans suck and aren't that accurate but should work if you get the right amount.
Btw 2 small cans is not enough for a front and rear system. I dont think you're adding enough especially with those pressures.

Another thing to help is to check superheat. Pretty easy on the front system. (Superheat is an indicator for how much liquid is in the evaporator and tells you how much work/change of state the evaporator is doing.)

Measure the line temperature right after the orifice going into the evap and measure outlet temp of the evap.
Subtract the inlet FROM the outlet. That is your superheat. If its really really high like 50F or even 30F, then you dont have enough refrigerant feed to the evap: ie low charge, restricted orifice. Superheat on a car should be anywhere from 0 to 20 once its cooled down.

Also (again sorry if i missed this) if you have rear AC. If the rear AC works pretty good but the front sucks or is warmer, you're low on charge. Rear system uses an expansion valve. Exp valves adjust and regulate themselves. The front orifice doesnt. So when system is low the rear will hog all the liquid available.

Hope this helps. Hit me up if u need more input man [emoji106][emoji106]
9cbc17f7763c5b009f75f2b060abb2d7.jpg


Sent from my SM-G975U using Tapatalk




I did leave that cap off for a good couple minutes until I realized it wasn't pulling vacuum hahaha!


I agree the pressures were low before I started messing with stuff but since the valve core was leaking I emptied the system, Vacuumed it for 30 minutes, then verified it could hold Vacuum for 15 minutes and began to fill the system. After putting just a single 12oz can in through the low side. The high pressure side shot way up to 450 with the compressor on. The high side port also got scalding hot and I was afraid it was going to burst.

Are you saying that more coolant will actually lower the high side pressure?

Yes it has rear AC and I did notice the rear was colder than the front as it was dying on my home. Never knew that was a symptom of low pressure though.

Thank you for the help! I know just enough to screw stuff up on AC:cheers:
 

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