idle problems

[240s13.5]

i'm a new guy to the whole nissan world, drove honda's all my life and decided i wanted something cooler, faster, and better looking, so i just bought a 1990 240SX SE with 220,000 miles on it. it runs good, but the idle is a little hard, i tested the fuel injector lines, and when i tapped them lightly, the engine bogged down quite a bit, but i don't know what else it could be. please any help, well is pretty helpful, thanks everyone.

whats done so far...-sleepy headlights-tore out the backseats