Just got done cleaning the throttle body, she looks very clean and shiny on the inside. put everything back together nicely, and went to start it, and it rumbled alot after I started it...like almost a V8 or sumthin, and then calmed back down after a while, but the rpm needle is still goin up and down around 800-850, but it's moving a lot. I noticed when I started her up again, she started alot smoother, but the idle rumble is still there where it jiggles my car a bit, and the rpm needle is still fluxuating....please help is that normal...what should I do? What should I check? Did I not tighten it down good enough? Did I tighten too much? HELP PLEASE!!!