2nd Gen Non-Engine/Transmission Can't find A/C leak, what next?

[Tinman]

I've had a slow leak in my a/c for years. Used to require about one can 134 per year. It has become much worse rendering a/c useless ( it might hold a charge for a week or 2). I've put 3 cans of dyed 134 and I can't find a leak. I've checked compressor over many times. Also checkedevaporator drain. Nothing. Any suggestions before I start throwing parts at it.

 

[tripl-e]

I've had a slow leak in my a/c for years. Used to require about one can 134 per year. It has become much worse rendering a/c useless ( it might hold a charge for a week or 2). I've put 3 cans of dyed 134 and I can't find a leak. I've checked compressor over many times. Also checkedevaporator drain. Nothing. Any suggestions before I start throwing parts at it.

You might not find dye evidence at the evaporator drain. I would not rule out the evaporator coil until I'd had a look at it directly. The oil/dye mix is pretty sticky stuff and could be clinging to the evaporator coil fins without ever 'draining' off.

 

[DavidC]

The way I found the leak on my Daughters and my 99 was with a sniffer I purchased from Amazon. The keys using a sniffer is to have the system fully charged and in a area where there is no wind. The daughters was the clutch seal and mine was the low pressure schrader. The sniffer has a flexible probe that can be fed into the air box to check for a leak in that area.

Dave

 

[Tinman]

I figure it's probably the evaporator just because I had the dash off a few years ago to replace the heater core. I should have done them both, but it didn't cross my mind. Where does one get a "sniffer", local auto parts store?

 

[DavidC]

I figure it's probably the evaporator just because I had the dash off a few years ago to replace the heater core. I should have done them both, but it didn't cross my mind. Where does one get a "sniffer", local auto parts store?

This is the one I have, a little pricey but cheaper than constantly adding freon and/or paying a garage service. Maybe cheaper on ebay etc.
http://smile.amazon.com/Inficon-TEK...e=UTF8&qid=1426962502&sr=8-2&keywords=inficon

Dave