Reviving this post as I happen to experience the same problem. I haven't really noticed if related to A/C but I definitely have some, apparently random, idle dips of ~500rpm. What worries me is that a couple of times (one of which a week ago), the RPMs dropped like the engine was about to die and then revved back up to normal idle. I will keep an eye if this happens also with A/C off.
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2013 PW 370Z Touring+Sport, NAV
Tint 35% side, 18% back | RJM clutch pedal | ZSpeed SS lines | Stillen Gen3 CAI | Fast Intentions HFC and TDX 12'' CF CBE | UpRev
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