Automotive Air Conditioning Information Forum (Archives)

El Dog on Thu July 31, 2014 12:11 AM

Year: 2001
Make: Cadillac
Model: Eldorado
Engine Size: 4.7 L
Refrigerant Type: 134a
Ambient Temp: 85
Pressure Low: 70
Pressure High: 0
Country of Origin: United States

On my 2001 Eldorado, charging my ac. I am new at doing this.

My gauges should read, with ambient temperature at 85 degrees, about 40-45 low (suction side) and 170-180 (high side), according to the book.

Getting "Low freon AC off". So, I put the gauge on the car and get 20 on suction and about 25 on high side. I clear the codes on the OBD and the freon starts flowing in nicely.

The low gauge goes to about 70.
The high side does not move above 25.

I think everything is hooked up right.

Low, suction, (blue hose on gauge) is the larger line that gets cold.
The High (red gauge hose) is the small line that gets hot.

Codes keep coming back with low freon and ac shuts off.

Any ideas?

mk378 on Thu July 31, 2014 9:28 AM

Find and fix the leak first. Leaked down to 25 means there is a major leak-- simply charging is going to be futile, it will leak out in a few days or weeks.

When charging you should try to first get liquid refrigerant into the car with the engine off. Then there is less running the compressor with a low charge.

Possibly the high side hose is not coupled to the car fully. The high side can never actually be lower than the low side, since that situation would just blow through the check valves in the compressor and equalize.