Ok everyone, this is hard to explain so bare with me, usually when my enigne first starts and its cold it will hard idle (jump from 1,000 rpm to 1,550 rpm back n forth) until it gets warm at which point it will stay at 1,000 rpm. Lately it will Hard Idle the whole time, this is not very good. My cousin said it could be a vacuum leak and that i need to find it and replace it, what the hell is a vacuum leak and how do i fix it, they want 60 bucks an hour jus to diagnose the problem, they said that its probably my cold start which could cost 40 buckx to replace and 50 buckx for the part. What is it exactly and how can i fix it myself.. somebody please im in desperate measures