Today as I was washing my engine I noticed my 4-2-1 headers on one of the bolts it didnt have a nut, it was between the 4 and 2 pieces they have three bolts and nuts that hold the header pieces , I KNOW the guy did everything correctly when he installed everything on, is it normal from time to time to have the nuts or bolts loosen up because of the heat? or where they maybe unproperly torqued? tomorrow i have to do some maintenance on it, does anyone know the possible size of the nut and bolt? im going to some how stick some socket on the back ones to see the sizes... looks possibly like 14mm.

 

yes sometimes they do get loose, and if they got loose enough they would completely fall off.

 

thanks lightshow, i torqued a 14 mm nut today all solved, the other nuts were tight on too.