i had the mpfi swap done to my civic and i was just looking around in the bay and found this hose with a plug in it. the hose comes right off the left side of the intake manifold. help me out or point me in the right direction please!!! and thank you

 

it would go to your fitv, but you already have a hose there.. interesting lol. is your intake manifold not stock? for whatever reason you've got an extra coolant hose that so far as i can tell is not needed.

 

there is a small pipe that routes that to the FITV. the one attached to the FITV was put there in it's place. Whoever put the aftermarket intake on got rid of that piece that also attached the intake arm to the breather tube on the valve cover. look for pics of an unmolested engine bay and you'll see what I'm talking about. It's confusing

 

even though that metal piece is missing it doesn't explain the 2 coolant hoses coming from that area. heres a pic of my engine bay. notice how even with that the piece, it wouldn't be using the coolant hose that op currently has his fitv connected to

 

my rex is the exact same way...everything is hooked up and working except for that hose, i did the same thing put a plug in it and left it, i used a z6 manifold and there was no way to route it..

 

I think the in one your hand goes to the FITV and the one hooked up to it must have gone to an oil cooler that some cars came with??

 

well i ask because starting yesterday on the way home my car started to jump up to about 800-1000 rpm's at a light. then after 3 or 4 seconds would drop down to normal. i was looking around and found that hose just hanging out........ i thought maybe it had something to do with it

 

my manifold is off of a d15b... i thought they all were the same?

 

when i multiported my hatch i had that hose hooked up and working, but when i multiported my rex that hose served no purpose, maybe cause i put a gsr throttle body on it...never could figure out why that was....but my rex idles fine, doesent hunt or nothing..

 

hmm im gonna try a new o2 sensor today at lunch and see how it goes