Where is the idle adjustment screw on a 1990 Honda Accord?
It is right by the trottle plate near the intake tube. The screw is item (1) in http://web.archive.org/liveweb/http://www.hondaautomotiveparts.com/auto/jsp/mws/catimgs/13sm401_e01.png Unfortunately that picture does not show quite where the screw belongs. Assembly (6) is held on by 4 studs and nuts. Starting from the top nut closest to the passenger compartment, go about 1 inch towards the front of the car and then about 1/2 inch down, and there it is. The figure shows a cap blocking access to the screw, and there should be one there if someone has not removed it already. If you are looking from above the engine, your view will be mostly blocked by the vacuum lines (29) above it. You do not need to remove the air intake tube to see or access the screw, but it is easier to find the screw with the tube off.