AC intermittent issue

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Mobirdie

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Minneapolis
Ram Year
2018
Engine
5.7
I’m having some trouble identifying the cause of my intermittent AC issues. I have a 2018 1500 Big Horn and I’ve been driving it about 100 miles a day and as the weather warmed up I’ve been turning on the AC. It was working fine for the first few weeks and started to now blow very cold for the first 30 minutes of my drive. The last 20 minutes it would start blowing cold again. As the weeks went on it was weaker and weaker. This past weekend I took it on a 400 mile road trip and I would have to turn it on and let it rest for a minute when it was blowing warm. I’d turn it back on and it was slightly cooler. During the drive there was a little noise coming from the vents and some little white flakes came out of the vents for a second. My friend said he thought it may have been ice since we couldn’t find it anywhere inside and the floor mat has a few water drops on it. It has not happened again since. Haven’t had time to take it in to see if it is just running low on Freon and I have a small leak or if there is a more serious issue. I had checked my cabin air filter and that was clean. The ice coming out of the vents has me a little concerned but at this point I’m waiting to take it in to get looked at until I can find something on forums somewhat relating to this. Any thoughts or suggestions would be appreciated.
 

Zorin

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It's very likely that you are low on refrigerant. (We don't use the term Freon anymore, this is the trademark name for R-12).

When you get low on refrigerant, the evaporator core under the dash will literally freeze up, and turn into a chunk of ice. It normally takes a while to do this, around the 30 minutes that you state. It is also consistent with seeing ice come from the vents.
The first thing I would do, is connect a recovery machine, and recover the refrigerant, and the machine will tell me how much it removed. Right there I will know if it was low on charge. If it was, great, we will re-charge to the proper amount and re-test.

If the problem re-occurs, at that point I would connect gauges, and check pressures, looking for a bad TXV. (Thermal Expansion Valve.)

Tim
 

MRFREEZE57

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pacific northwest
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It's very likely that you are low on refrigerant. (We don't use the term Freon anymore, this is the trademark name for R-12).

When you get low on refrigerant, the evaporator core under the dash will literally freeze up, and turn into a chunk of ice. It normally takes a while to do this, around the 30 minutes that you state. It is also consistent with seeing ice come from the vents.
The first thing I would do, is connect a recovery machine, and recover the refrigerant, and the machine will tell me how much it removed. Right there I will know if it was low on charge. If it was, great, we will re-charge to the proper amount and re-test.

If the problem re-occurs, at that point I would connect gauges, and check pressures, looking for a bad TXV. (Thermal Expansion Valve.)

Tim
This is very likely what is happening, need to put a set of gauges on and see what is happening.
 

RamCares

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Hi Mobirdie!

If you do choose to take your vehicle to your dealer for diagnosis, please feel free to reach out to us here via a private message. We're happy to help!

Callie
Ram Cares
 
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