fluctuating idle caused by what?

[exzeltus]

My idle on my 98 gsr fluctuates. I don't mean it fluctuates b/t 1200-600 when I start the car in the morning.

I mean on different days it idles at different rpms. On some days its 600rpm. On other days it's 1000rpm, and it just varies.

Is this normal?

I don't know if this has anything to do w/ it, but i'm new to manuals. So I drive differently everyday I go out and drive. Like one day, I won't go over 4000rpms. On others, I shift at 6-7000rpms. I do this to teach myself how to shift at different rpms. And this is how I learn.

[JAYMAN320]

the temp of the day could cause it to do that, or maybe you just need a tune-up