My engine revs at random when i'm stopped, I was wondering what could be causing this. It's a 1997 blazer with 200000 km on it. It's my first car, so I want to make t run for as lo g as possible. I thought it was the spark plugs, but I could be wrong. Any help will help

 

It could be a vacuum leak. Look for any cracked or missing hoses at and around the intake.

 

I didn't think of that, thanks I'll see if that fixes that

 

on my 2000 ls ive noticed it will randomly rev up when its down shifting to come to a stop. It will rev and jerk a little...but not all the time. not sure if its the same as you're problem.