I charged my AC "2 cans" tuesday night on my 95 Bonne. I noticed when I turned off the car I could hear a short high pitch squeel coming from the passenger side...only last a few seconds...now my ac is blowing warm air again. Is there a sealant that I can put in to seal any pin holes/leaks in my ac before recharging it? any ideas? thanks, Mike

Hi Mike,
I have a few questions.

When you say "high pitched squeal", are you refering to a mechanical squeal or a sound caused by a high pressure leak?

Was the sound inside the cabin or from the engine bay?

And lastly, did the sound occur AFTER you shut the car off completely?

Now, there are some leak sealant type products to be had at your local auto parts store, but a loss of 2 lbs. in less than two days is not a small pinhole leak. You have something more serious going on, IMO.

The squeal sounded like it came from underneath the hood/passengerside. It sounded like an air leak...like air escaping from a balloon...

I used one of those products that seals AC leaks, and it worked for a bit (a day or two), but then the temperature flashed yet again, and the leak was back again. So, I say, use at your own risk

With a sudden leak of that size, I highly doubt that a stop leak product will give you lasting (if any) good results. A/C stop-leak products are more suited to small gradual refrigerant losses, IMO.

Also, you should look carefully at the A/C lines and the A/C compressor area and look for dark smudges/areas where the PAG oil will indicate where your leak is. Pay particular attention to the compressor as blown compressor seals are a likely culprit.

If you're not up to the task or cannot find anything, I suggest a local A/C shop that will do a system analysis (often for $25-35).