OBD1 B18B1 in a 98 civic coupe ex. I bought the car already swapped, but the person that did it did a HORRIBLE job. So I'm going through and doing it the right way. My question is, I've noticed on a couple integra's and civic's at the junkyard that they have a lot more hoses in the bay (I'm assuming it's the vacuum system) than my civic does. What is the point of all those vacuum lines? And are they necessary/should I have them? My car came with the entire vacuum system, power steering, AC, and cruise control deleted. Also, my EVAP system is not hooked up (Not sure what that is for either).

 

importantly you need vacuum lines for the brake booster, the PCV system and fuel pressure regulator.

 

If you have a leak, it will probably idle funny, and hear a hissing sound.

 

They keep your engine bay by sucking excess dirt into the engine. Honda, by hoover.

I know some cars (probably not integras) also have vacuum assisted clutches, and vacuum adjusted suspensions. Older cars even used vacuum to power windshield whipers.

My advice: Determine what hoses go where, determine which ones are unnecessary (if any) and use a vacuum block on that hose to prevent vacuum leak.

 

vacuum is only really important for the MAP sensor (if firewall mounted), brake booster, FPR and that's it I think. The PCV and evap system can be deleted, you should just run a catch can if you delete the PCV system. Otherwise you get excess crankcase pressure.

Just get little caps to plug stuff. $2 or so at any store and they work.

 

Well I have the brake booster, and FPR vacuum lines hooked up still. And the PCV line is replaced with one of those little breather filters you can get at o'rileys for like 10 bucks. The main thing I'm wondering about is what looks like a box with a bunch of hoses going into it. I've been told its not necessary, but I'm just double checking. Also, where does the vacuum line that comes out of the front of the intake manifold, and goes down between the air inlets for cylinders 1 and 2 go? The line was disconnected and plugged when I got the car, so I just put one of those vacuum caps on it to clean up my bay a bit.