Air Conditioning problem
2000 GMC Sonoma 6 cyl Two Wheel Drive Automatic 95000 miles
I have a 2000 GMC Sonoma V6 4.3L. I got the truck at like 40,000 miles 7 years ago, A/C worked fine except it used a lot of gas and robbed engine power. So I used my a/c sparingly. After a while, I never used my a/c. At the most I turned it on maybe once a year for a few years. For the past 3-4 years, I would turn it on like once a year to see if it worked. I heard the clutch come on, but over the years it began to blow warmer air. This past week, I wanted to see if I needed just a recharge because I am going on a trip. I turned on the a/c and the clutch wouldn't engage now. I bought one of those recharge kits at and auto store, and my friend helped me out. Put a little bit in and the a/c clutch turned on, but it appears that I already had enough refrigerant. Do I need to evacuate the system now and start with new refrigerant? Because it doesn't blow cold air.
You probably do not have enough freon in the system yet.
One can is not enough, and the only way to tell is with a manifold gauge set attached to read the high and low side readings. Clutch cycling frequently? That means freon is low.
May, 8, 2010 AT 11:51 AM
My only problem with adding more refrigerant, is my pressure is already where it should be, and yes the compressor is cycling frequently. I don't want to overcharge my system. That is why I am wondering that since I rarely used my a/c, I didn't let the oil and refrigerant circulate. Should I go get it evacuated and recharged?
May, 8, 2010 AT 11:14 PM
If it's cycling frequently it means the low pressure cutout switch is detecting low pressure, this happens when there isn't enough freon, add more. USE manifold gauges, not refrigerant bottles with a dial.