Automotive Air Conditioning Information Forum (Archives)

86gtconv on Wed August 04, 2010 6:26 PM

Year: 2001
Make: chevy
Model: suburban
Engine Size: 5.3
Refrigerant Type: 134a
Ambient Temp: 90

The front AC has been slowly getting warmer and now it is warm. The rear AC is cold though. the line going into the Evap on the engine side of the firewall is very cold, but the larger line coming out at the firewall is warm. It is as if there is a 'plug' somewhere. Any ideas? can the evap just get stopped up on the inside? I tried checking vent temps with the AC off to see if the heat was somehow on, but they were around the ambient temp. When the AC is running the vent temps were slightly cooler by 3-4 degrees.

Thanks,

Jim

mk378 on Wed August 04, 2010 6:56 PM

That happens when there is a leak. There is no longer enough refrigerant to fill up the front evaporator and make it cold.

86gtconv on Thu August 05, 2010 9:20 PM

I was able to add some dye and 134a. I added freon until the High side was around 200 and the low was around 40 with the rpm's at 1500 and the temp was 89. The vent temp on the front hovered around 68 and while the vent temp on the rear was around 49. Sure seems like a larger difference. Any ideas why this would be the case?

Thanks.

Chick on Thu August 05, 2010 9:50 PM

You need to find and fix the leak, but I would evacuate the system and recharge (with the dye in there) by weight, cooling will return to normal, topping up a system is not easy for a DIY'er..

-------------------------
Chick
Email: Chick

---------------------------------------------

Freedoms just another word for nothing left to lose