i just dropped a b16 in my 91 civic si and i'm having a problem with it running right. on the back of the manifold where the idle control valve is. on top of the valve i see a hole. what is it there for. on the diagram i have it shows that a vacuum line goes that ,but on my manifold i only have a hole no tube for the vacuum line to hook up to what shold i do. will that make my car run rough

 

Any vacumme leak will cause your car to run like poop if it runs atall.
I don't have a diagram in front of me, but it goes somewhere, or it needs to have a cap on it so it isn't releasing vacumme pressure.

 

booster, pcv, fpr, and map require vacuum. Remaining vacuum ports should be capped.

 

Wow that's really weird. I have nothing but two coolant lines and the electronic plug on my iacv.

 

it right above the iacv i have a diagram and it show that it goes to the purge cut-off solenoid valve. on the diagram i have it shows two purge cut-off solenoin valve ,and on my car i only have one what can i do about that ans yes it will start but take a long time to start

 

I dont think that the other one is a purge control solenoid. I have to double check my helms about that though. Nevermind it's not. Heres the diagram.

https://honda-tech.com/zerothread?id=1293285

I guess you could try plugging it or you could go to a junkyard and get one and then install a vacuum line plug into the hole that is missing one.

 

if you look at the pic on to of the iacv the line with the 10 on it, on my manifold there is no little pipe sticking out there just a hole with thread like something there is something that screw in should i just put silicone of the hole