AC refrigerant loss

Had a lot of smoke/vapor coming from the passenger side. Pulled over and turned off the car. Lots of hissing/smoke for a while after shutting off engine, coming from under the passenger headlight. No CELs. AC no longer blows cold.


Pulled off the rad support, the only thing out of place is this connector that was unplugged.



Don’t see any cracked lines. Anything else I should be looking for? I’m guessing first step would be a pressure test?



Edit for anyone searching: The unplugged connector attaches to the high pressure switch. It got blown off when the switch failed. I replaced the switch and receiver drier. Spoke to an auto AC shop, they said the oil should mostly be retained in the system still, and advised to only add 1 ounce or so.

drval85 said:

Had a lot of smoke/vapor coming from the passenger side. Pulled over and turned off the car. Lots of hissing/smoke for a while after shutting off engine, coming from under the passenger headlight. No CELs. AC no longer blows cold.


Pulled off the rad support, the only thing out of place is this connector that was unplugged.

Don’t see any cracked lines. Anything else I should be looking for? I’m guessing first step would be a pressure test?

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When my compressor seal gave out, there was a distinct smell of refrigerant oil and a small oil leak under the compressor. There are less or trace amounts of refrigerant oil in the AC liens the further you get from the compressor, so if it is a small leak you may have to add dye the refrigerant in order to trace it.

Good Luck

Seems like the pressure switch broke, and rapidly dumped all the refrigerant.

I’m going to replace it and the receiver drier, but can I then pull a vacuum and refill? Kind of concerned about the remaining oil level in the system. Would I be better off with a full flush to remove all oil and then refill?

drval85 said:

Seems like the pressure switch broke, and rapidly dumped all the refrigerant.

I’m going to replace it and the receiver drier, but can I then pull a vacuum and refill? Kind of concerned about the remaining oil level in the system. Would I be better off with a full flush to remove all oil and then refill?

Click to expand...

The majority of compressor oil stays in the compressor, unless there is a hole in the casing or leaking from the seal for it to leak out. Replace the pressure switch and the receiver drier on the condenser, then pull a vacuum. When all the R134 leaks out you just and refill with the exact amount of ounces of R134, easy peasey in that respect.

The pressure switch blew violently, and all the refrigerant escaped quickly. There’s zero r134a left in the system. Took a lot of oil with it and sprayed it all over the engine bay. That’s why I’m unsure of the oil left in the system. Already swapped parts and ran a vacuum. Bentley manual says it takes about 110cc total, and 50% stays in the compressor. So I’m guessing I’ll fill about 60cc to account for some leakage, and keep the AC off until I can take it to a pro shop to drain/refill.

drval85 said:

The pressure switch blew violently, and all the refrigerant escaped quickly. There’s zero r134a left in the system. Took a lot of oil with it and sprayed it all over the engine bay. That’s why I’m unsure of the oil left in the system. Already swapped parts and ran a vacuum. Bentley manual says it takes about 110cc total, and 50% stays in the compressor. So I’m guessing I’ll fill about 60cc to account for some leakage, and keep the AC off until I can take it to a pro shop to drain/refill.

Click to expand...

I replaced my compressor with a used one(exact same model), used whatever amount of oil came with it, replaced the receiver drier on the condenser, vacuumed and refilled with a couple of cans of R134, calculated by weight.

Once you have a hole in the system and the R134 already leaked out the whole R&R is rather straight forward. Used a Harbor Freight AC Manifold and cheap HF venturi vacuum pump connected to my buddy's shop compressor with huge tank to pull vacuum for half hour.