just replaced my exhaust manifold on my 98 civic and a stud came off but thankfully its not stripped. how do i put it back in? i read "double nut the stud" what does that mean? fill me in plz

 

What that means is you put two nuts on one end of the stud, then tighten them together, what that does is it stops them from rotating on the stud, so then you can put a wrench or ratchet or whatever to put the stud back in.

 

is that the only way to do it? what am saying is i dont want to take the whole head apart just for one stud, there must be an easier way

 

That is how you do it. Then you put an end wrench on the bottom nut and loosen the top nut with another wrench (socket or end) and take the double nuts off, leaving the stud in the head. If there isn't clearance to do that you'd need to take the manifold off and put the stud in, but you don't need to "take the whole head apart", just take the manifold off.

The two ends of a stud are usually different. The end that goes into the head has "tight" threads that are supposed to stick somewhat, so the nut would prefer to come off instead of the whole stud unscrewing. So make sure to put the stud in the right way.

 

^ What mk378 said You should not have any issues.