Nissan Repair: nissan almera 2003 modle, nissan almera 2003, vacuum leaks

Question
my almera is cuts off wen ever the idle gage does idle low.
and whenever i start the vehicle it cut back off. sometimes the idle is high on mornings and then other times it is low. what can i do?

Answer
Jason,

The manifold absolute pressure sensor (MAP) is what the computer uses to determine idle.  The idle air control valve (IACV)is how the computer controls idle.  Basically, a pintle valve on a stepper motor.  If the car is in tune and the throttle body is clean the system should operate properly.  Bad plugs and a dirty throttle body will cause the engine to have a low idle and even cut off, as you describe.  I would make sure the tune up is recent and the plugs are good.  Next, clean the throttle body.  Once this is done check for vacuum leaks like bad hoses and gaskets.  If you have access to a scanner get the codes read.  Any codes correct the problem(s)  Now, it can only be the idle air control valve or the MAP sensor.