My 2003 L200 2.2L has started to surge ~1500RPM whenever I turn on the A/C. It'll last for 5-10s and then stop for a minute before cycling again.
The A/C is charged and the air is cold while this is going on.

I've read a long list of possible explanations for this and am at a loss on where to start.

So far, I've cleaned the throttle body some and the MAF sensor. A few months before this started, I did have my brake boost replaced (vacuum related?), but the A/C has been working fine during that time.

Is there anything specific to these Saturns that might give me a place to start looking?

Thank you

 

The computer anticipates compressor load and strokes the idle air control valve before it engages the compressor. It is supposed to be not noticeable to the driver. Do you only notice this surge at idle? Or do you also feel it while driving down the road? I suspect a problem with your idle air control valve, it is mounted to the back side of the throttle body. I have not had this problem with my car, I do have a 2002 factory service manual set if you have any codes. Do the cooling fans operate properly with the air conditioner?