i need HELP please?
 

i have a stock 1988 turbo supra and it idles at around 550 rpms and it seems to lower then higher at random times. i would like to know if i could adjust the rpms or not? any help would be needed.

The idle is computer controlled and not to be manually adjusted. If the idle is wandering like that there are a few possibilities. I suggest you begin with checking for diagnostic error codes (covered in the FAQ section) and inspect for leaks in the intake plumbing, PCV and vacuum system.