So i was doing an oil change yesterday. When i was about to remove the oil filter i saw what looked like a hose fitting on the back of the intake manifold. i circled it in red, i have no idea what this is and whats supposed to be there. can someone enlighten me. it seems to affect the engine when i put my finger over it, it causes the rpm's to drop. if there is supposed to be something there, i have no idea why it isnt.

I Drive a 2000 Civic EX

 

goes to evap solenoid, which goes to charcoal canister

 

Wrong diagram its for cruise control

 

oops, i have the first gen EK pic

anyways OP just cap it off if the cruise has been removed. if not, reconnect it!

 

thanks a lot sleeper. i found a hose that was disconnected. connected the hose and all is good.

thanks again