i've narrowed it down.....gotta go to a shop, but am still looking for any suggestions, reasons, etc. '99 5.2 durango is the vehicle, 'interdynamics' A/C repair 'stuff' & my own big hammer is what i've been using. actually, have converted MANY old-school REAL freon auto A/C's to 134a, & have refilled many newer 134a vehicles using 'interdynamics' stuff with excellent results. have refilled this particular durango with 'inter-D' products twice before, once about 5 years ago it took less then a 13 oz can to get pressure on THEIR cheapie guage to show 30+ psi, and 2 years ago i used one of the 'special' maxi-cool or something like that & had ICE COLD A/C for 2 summers after. last winter i had to change the water pump & am pretty sure i was careful with the A/C compressor, but, in last weekends steambath, my A/C was blowing HEAT. well, i used my trusty 'interdynamics' hose & guage with a 17 oz can of their 134a & oil mixture & -0- psi went right up to mid 30's & A/C was COLD. lasted 3 days & pressure dropped to 'low in the green' & cold air wasn't forthcoming. i tried one of their sealants with dye & a refill. saw NO leaks & A/C was cold again, but, now 2 days later, i have low psi again & cold air is just about gone. any suggestions???

 

Evap has a hole in it. Popular failure as the vehicles are getting older.

Get a shop to stick a probe in the center dash vent. Turn on the air and listen for the probe to beep indicating the hidden freon leak.

Then spend 3 days, tons of work and $650 in parts to pull out the dash and replace the evap, heater core and blower motor. Your could find a shop to do the labor for another $500-800 or the dealer to do it all for $2500+

You want to replace all three comsumables, the evap/core/blower motor because you do NOT want to have to pull the dash again and again to fix each as they fail one after another. Get them all done at once.

Here is my adventure down this same yellow brick road:
http://www.durangoclub.com/forum/viewtopic.php?p=92837&

IndyDurango

 

+1 for Indy's response. I had to have my heater core replace not under warranty and the labor to for teardown and put the dash back together was easily an all day job. Labor cost for a friend of mine to do it was $300 but I can easily see a much higher price if you took it to a dealer. My A/C was still brand new so I did not have to change that out when I replaced my heater core.

 

+2

You gotta leak somewhere. Don't install more oil unless it leaks out.

I don't like stop leaks period!