Idling fluctuates from 500 to 1000 loud and smokes and I have to keep it around 1500 to be somewhat smooth. It smoked up my garage in 2 minutes.
I have to push very softly on the gas pedal past 2500 and between 4500 rpms to keep it "healthy"
My friend claims to have seen me shoot a massive fireball while driving to my mechanic!

Any ideas what could cause this?

thanks in advance

 

Well, it was a loose vacuum line to the map sensor.

What is the map sensor?

 

Don't worry...you're not the first to have that happen.