The idle control valve is on the left side of the intake manifold right next to the throttle body. A short hose connects from the valve to the intake air tube in front of the throttle body. The valve has two adjustment screws: one for normal idle and one for fast idle, such as when the a/c is turned on or the power steering is turned.
Assuming you have a mpfi engine it is in the throttle body.
it is located on the side of the transmission
check your idle air control unit also called an IAC motor
http://www.ecklerscorvette.com/corvette-hot-water-control-valve-for-cars-with-air-conditioning-1986-1987.html
non-turbo: 160 turbo: 185
yes, look at youtube they have somw examples.
The Nissan 300zx has a gas tank that holds about 19 gallons. The 300zx gets 19 MPG in the city and 24 on the highway.
the idle should be about 900 RPM in park or neutral.
On my '86, 300zx NA, the rocker switch on the console turns on the heated outside mirror (drivers side).
Go to Carfiche.com. They have the entire schematic for the 86 which is the same for 85 with the exception of engine compartment. Then the only real difference is that they added an Air injection valve. But as far a wiring goes I believe that the wiring is the same for the 84-86 years. Hope this helps. By the way the download is free.
in the left side leg clutch pedal there is a square cover. rigth there is it.
1985 - 1988 Nissan Maxima is the only other Nissan model with power window motors that will fit a 1986 300ZX.