My AC hasn't been working for sometime now. So yesterday I went out and bought a Recharge and Restore Kit from Auto Zone. The kit came with three cans of R-134a refrigerant and a recharge hose with built-in pressure gauge. I ended up putting 2 1/3 cans of refrigerant in my car. To make a long story short, sometimes my AC works and sometimes it doesn't. I did notice that when my AC is not working my radiator cooling fans cut off and it will cut back on but it only stay on for about 5 seconds (if that). When it’s working the fans stay on all the time.


What could be causing my radiator fans to randomly malfunction like this?

 

It only takes two 12 oz cans of R134a to fully charge your system. From empty.


So........, if you had any refrigerant at all in your AC system when you started, adding 2 1/3 cans will certainly result in an overcharge.

You cannot simply begin adding refrigerant to a system without first diagnosing what exactly is going on. Was the system in fact empty when you started? Did you pull a vacuum on it? Is your compressor clutch engaging? What are the low & high side pressures when it is running? I realize you are concerned with the cooling fan operation, but that may well be a secondary issue.

 

Now I am really nervous. Right off hand I don’t know what the low and high side pressures are, but I did follow the directions from the kit. Basically the instruction told me to check my system and add refrigerant if I need it. I didn’t pull a vacuum on it, was I supposed to? I am not even sure what the compressor clutch is, but now that I think about it, I do hear something click on an click off when my cooling fans cut on and cut off. Is that the compressor clutch engaging?

I just read that an overcharge will affect system performance and that most cars have a feature that shuts an overcharged AC system down in hot weather. That would explain why yesterday morning my AC worked and for my commute home. However, when I went to go workout it stopped working again.

 

There's nothing wrong with your a/c fan. It should only be on when the a/c compressor is engaged!

 

+1

From what little I know with electric fans when the ac is on the fans stay on and when the ac is off they are controlled by the temp of the car. somebody correct me if I'm wrong.