So i got a civic here in PH which has a D16 block p2j Head and p2k intake and it was idling pretty bad with the p06 ecu coz i havent got it tuned so i swapped in the stock one which is the p2m one and it idles good but when i turn on the A/C the rpm drops significantly and when i turn on the headlights the rpm will drop also but not that big. And i was trying to figure it out watching tutorials on youtube but i just cant seem to get it right, so a little bit of help might do

Things ive done so far
-Tightened the IACV bolt all the way
- Adjusted the Air intake screw, tightened it all the way
-adjusted the distributor timing
-checked mechanical timing

Please halp
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By turning on the AC, you are adding load to the engine (force required to turn the compressor and electrical load for the fans, compressor clutch, etc on the alternator, which adds more physical load to the engine).

By turning on the lights, you're adding load to the engine (electrical load on the alternator, more physical load on the engine).

What is your fully warmed idle RPM with AC and lights turned off? What is it with AC and lights on?

You mention that you haven't gotten it tuned. What engine management are you using?