Nissan Repair: airconditioner idle adjustment, air control valve, absolute pressure

Question
Normally, when you turn on your a/c, the idle should increase.  With my 94 altima, when i turn on the a/c, the idle decreases and sometimes causes the motor to die out. How can I adjust this idle o increase?

Answer
JR,

The airconditioner, when it turns on, causes a load on the engine.  The computer compensates for this by the use of a manifold absolute pressure sensor.  It detects an incerased load and sends a signal to the idle air control valve.  I would think the idle air control valve is stuck and unable to increase idle air entering the intake.  This will cause the idle to drop and the engine to die.  I would clean the throttle body and remove and clean the idle air control valve along with the passage.  You might need to replace the idle air control valve if it is not moving properly.