Nissan Repair: loss of power on 1996 Nissan 200sx, nissan 200sx, loose power

Question
I am driving this car every day to work, and sometimes it feels like it lost power, specially when the A/c goes on, but sometimes the car runs perfect and I dont notice if the A/c goes on or off.I've  replaced the spark plugs and wires,rotor , and rotor cup, but the problem continuos.

Answer
Dario,

It could be that the compressor is getting ready to go and the bearings are binding up or the impellers are binding.  If this is the case you can verify it by running without the airconditioner on.  If the car does not loose power you know that it is the airconditioning compressor.

It could be that the ariconditioner has nothing to do with it and the car just needs a tuneup or a fuel filter change.  I would start with a good baseline like a tuneup if yours has not been done in the past year.  If it has check the fuel pressure to see if the fuel pump is not going out.