exploded line

I started my second xj the other day and it ran for a second or two and then I saw a bunch of smoke.
I turned it off and I think my tranny cooling line exploded or something. it sprayed trans fluid all over my header and made smoke. im not sure what line it is but it starts out as a hard fitting, then turns into soft line, then goes back into a hardline.
does anyone know how much or what this could be.
it is an 88 4.0 l6 also.

On that side of the engine in rust free California where your trans, fuel and brake lines are probably not all rusted too nothing I would guess your power steering pressure hose blew, Probably $25 at any local parts house.

That is your low pressure transmission cooler line.