Issue with my Air Conditioning?

[Longboy]

So a few days ago, I started to have some issues with my A/C. The issue is that it'll blow cold for a little while, then switch over to warm (like the A/C is off), then it'll switch back over to cold again. It doesn't do it every time I drive my car with the A/C on. Only from time to time. My uncle who is the previous owner of the car said it sounds like the Evaporator freezing up. What does it sound like to you? Has anyone else here on the forum had this issue? Any help is appreciated.

[me109]

My evaporator used to freeze over. Airflow through the vents would gradually reduce to zero, but the temps were always cold.

Sounds like you might have insufficient airflow through your condensor, or not enough refrigerant. Does it tend to warm up while you are stopped?

[Longboy]

It does warm up but not by much. I believe something is going on with the compressor as well that might be contributing somewhere along the lines when it comes to the A/C problems.. There is a clicking type noise coming from the the compressor area. It only does it when the A/C is on. This heat wave we had over the past few weeks has really put a strain on my Mazda's A/C system.

[me109]

Yeah I once had a rebuilt compressor with that clicking noise. It didn't last very long. You could try adding oil, but likely the damage is already done.

[Longboy]

Great. But then again, the truth is ugly at times. I don't know if the compressor or evaporator is stock to the car or not. While thats basically beside the point...it sort of shows just how well Mazda made the Proteges, at least in my opinion. If the parts stock, then it doesn't surprise me that the mentioned parts are acting up. If I was to add oil, where would I add oil at exactly?

[me109]

Directly to the compressor at a refrigerant port, so you would have to remove a line from it and then recharge. It might be low on refrigerant anyway.

[Longboy]

Quite possible when it comes to the refrigerant. But it sounds sort of hard in my opinion. But that's why I'm glad I'm a part of this forum. I'm thankful for anyone's help and pointers. Where can I get the oil?

[me109]

Parts store. You will need to know if you have R-12 or R-134a in the system now because they take different oils. You can vent the refrigerant from the schrader valve, but it's better to recapture it with proper equipment. Once the system is depressurized, you can remove a pipe from the compressor and add oil.