need mechanic

Yesterday I bought a 99 mustang, and it vibrates quite a lot while idle and while diving. What could cause this and what are possible solutions?

Hello guys, I'm new to this and it's my first time on a forum. I really need some help please... I just bought my first mustang. I'm super excited. It's a 2002 Mustang GT V8. 127k miles. There's an issue with it tho. When the mass air flow censor is plugged in, it idols ROUGH, and runs ROUGH...