Ander,

Sounds like it is working normally. Mine idles near 900 rpm in neutral and around 700 rpm in gear, BUT my idle contact switch is disconnected due to problems with the air flow meter. There is a plate or emmission sticker under the hood that states where it should be idling. If it is running fine, don`t worry if it is a bit off, drive and enjoy.

Tinker
87 16V Auto