engine hesitates, any ideas?

[Orcajin]

hey there folks,
got me a 1991 nissan 240sx
with the KA24DE in it, all stock


ok so what happened is, i changed my serpintine belt. and that went fine, everything was cool

but my fan shroud is shredded to shit, and when i put on my intake manifold i neglected to secure my vaccum lines

and when i was driving i ended up getting my fan shroud caught in my radiator fan, taking my vaccum lines with it, i had severed one of the vaccum lines, but soon got it replaced
well, as soon as my fan shroud got caught, the engine started to hesitate at about 2.5-3k rpm, and its been doing that ever since.
im more than sure its some vaccum problem, because the engine didnt start to hesistate until the vaccum lines got caught in the radiator fan.
well, my dad thinks it might be my vaccum advance?? or something similar

anyone have any hunch as to what it could be? any advice would be awesome, thanks

[s14xman]

I would just make sure you check all the vac lines espesialy the small diameter one on the underside of the intake, which is easy to miss. Also check the MAFS wiring to make sure it didn't get loose or frayed. Hope this helps. Maybe take a picture and post it as well