01 sunfire a/c not working

Did you replace the orifice tube?

There are simple conversion kits that basically just replace the service ports to use the r-134 type hoses, but it is best to have a pro evacuate system and flush it, draw a vacuum, add correct oil and freon. If the system has been empty or dead a while, best to replace dryer and orifice tube or expansion valve as well.

Look for a light blue label in the engine compartment, the refrigerant capacity and oil capacity are on that label. But, being a '97, that label might be long gone. That information can also be found in a service manual. Manuals can be purchased at parts stores and you might even find one at a library. You could also call a dealer's service department and ask them.

11 OZ of PAG 150 oil Follow Compressor instructions to see how much to add to New Compressor and the balance should be poured into the NEW Accumulator and change the orifice tube in the front near Y split after the condensor on the high pressure side.

It cost me around $220 for parts from AutoZone (AC Compressor, Accumulator, Orifice Tube, and Refrigerant Oil). I had to have it professionally evacuated and charged by Firestone and that cost me $80. I didn't flush the system because my compressor didn't blow up and throw chunks out. I made a video on how I did it. So far it's working great!

di you replace the orfice tube; drain the system of freon, and recharge the entire system, and put the pag oil back in? If this was not done, your system will not work, because of an auto shut off valve.

You were not clear, but I assume the compressor runs OK. If not, troubleshoot the electrical to the compressor. Did you replace the orifice tube while it was discharged for service? If not, then check the pressures. If low side pressure is high the tube might be plugged, especially if you truly had a bad compressor. In a properly working system the line should be cold on the evaporator side of the orifice tube when properly charged. If compressor runs, system properly charged and that line is warm then suspect a plugged tube.

The oil spec is PAG 150--68.00 ounces. General Motors issues Bulletin # 02-01-39-004B replacing PAG 150 oil with a lower viscocity oil. Thus, now indicates PAG 46 (P46D) oil for those vehicles.
There is a high pressure side and low pressure side to the system. The high vapor=compressor to the condensor. Low side vapor=compressor to evaporator. Your system will use R134a freon.

The A/C is a sealed system and when the compressor fails it circulates debris throughout the A/C system and contaminates it. Before replacing the compressor several other A/C parts have to be checked or changed.
Typically, the condenser should be flushed to remove any debris or contaminated compressor oil. Use approved flushing agents (aresol or liquid pour types), that evaporate quickly and don't leave any residue in the system. You will also need access to 'DRY' compressed air or nitrogen to push the flush through the system. Nitrogen (an inert gas), is best because it doesn't introduce moisture into the system. You need to do this a couple of times.
Accumulator or receiver drier should be replaced when you are replacing your A/C compressor. If don't replace your accumulator or drier you will probably void your compressor warranty. It's virtually mandintory to replace the orifice tube or expansion valve. The openings are usually about .050" and are quickly plugged. Be sure to clean all hose assemblies internally prior to installing your new compressor. Not doing this could contaminate your new compressor. Flush both ways until the flush agent exiting is clean, you will need to remove the hose assemblies to do this.
After you have cleaned, inspected and replaced all the parts, you connect the vacuum pump and remove the air from the system. Make sure it holds pressure. Then recharge the system with the proper freon and oil to the system specified levels.

No matter why you are replacing the A/C compressor there is a lot of other related work that has to be completed before you install the new compressor. Hope this helps, good luck.