SOHC Vacuum line removal

[Fla240sx]

ok theres been a lot of talk about vacuum lines lately... and I myself was very interested.... and there are lots of vacuum lines hiddien around, lots of T's, and lots of confusion.........

I will make pics tomorrow when I have light!!!!

so I really sat down and took some time to figure out everything.... and came up with an extremely simple solution... Now I'm running the bare minimums... and thats all this how-to applies to.......

ok so its been said that all thats needed on the car is the Brake booster and the Fuel Pressure Regulator.......... I've taken the vacuum off of everything else and my car runs the same.... I cannot say yours will, I claim no responsibility for your work or your parts....

From my understanding, their are THREE hard metal ports that come off the intake manifold that provide vacuum... besides the big one for the Brake booster..... I took two of them and looped them together.... The ones by the throttle body.... I cut off a piece from one of the lines going to the Charcoal canister for this purpose... then just stuck the ends onto the two parts........ bam two vacuum ports easily plugged

Now the 3rd one..... and this is an easy one... just take another properly sized vacuum line, again I reused an old piece....... and routed it directly to the FPR

so in conclusion, I now only have 3 vacuum lines on the car, one that loops together two ports... one that goes to the FPR, and one big one on the firewall going to the Brake booster.......

you MUST also make a plug for the intake tubing to plug the vacuum line, mine is the stock plastic one... its the smaller of the two ports by the throttle body... I used a bolt pushed into it with some sealing tape that is kind of like tar around the head to seal it off completely.....

you can now go about removing anything else that runs off vacuum that you no longer need, in other words all the emission parts, and every other metal lines or rubber lines that hold vacuum that are no longer used..........

pics tomorrow, you can do this with some cutters, hell maybe even scissors, and about 5 minutes of your time........ its pretty damn simple! When you see the pictures of what I did, you will want to get rid of all those POS vacuum lines and emissions equiptment with a big smile on your face....

plus my header will be here next week hopefully and I can also gut the entire EGR and STUPID AIV system... which really cleans up the car a lot

[JOESCHMID26]

so wheres the pics? I live down here in boca my car doesnt idle that well i think getting rid of the egr will sovle it but its my daily driver so i want to make sure i can get it right in 1 day.

[Fla240sx]

this picture you see the two vacuum ports, as I call em, I looped together... I just took a piece of old tubing off something else that would fit these two, one is a different size I believe so you really have to squeeze it on.....



here I took a bolt and some tarish type material we use for A/C evaporator boxes to seal it off... use your imagination here, just use something that won't get sucked into the intake manifold.....



This is the port off the intake manifold where I took an old piece of hose and sent it to the FPR... which is located on the backside of the fuel rail... I couldn't get a good quality picture of it.....

in the end pretty much the only thing with vacuum going to it now is the FPR, as you can see... and the big line that runs to the brake booster......

[gumby74]

I must have pulled over 5 feet of vacuum tubing myself. Now that all that crap is gone, it really opens up the engine bay.But then, I am also running e-fans.And no, removing all this crap may not improve your idle. Try and find out the cause before you jump in. Lastly, assuming you are prepared, you can pull all this crap and do some detail work in a few hours.

[Fla240sx]

its amazing how many hoses there are on the car isn't it?

I had a good pile of useless **** when I got done

[KA24Power]

hey man, I am doing this on my SOHC right now too and just ran across your thread.. can you take a picture of your whole bay? I wanna see how its gonna look. (dont worry about lack of exhaust, mine is off right now as well as the intake)

I think it looks so much cleaner without all the useless emissions stuff. I bought vacuum caps and used them for most of my hard lines.

Oh, and what did you do with the hard lines that run under the intake plenum by the throttle body? There is a set of three and I think they run to the charcoal canister and the AIV. Did you plug them or take them right out?

[shpaintball]

excellent man very nice yea admin should stick this in how tos ...to replace the one they have currently this one is way better ...nice work

[KA24Power]

They shouldn't replace Fiznat's writeup, his is very detailed and good for the DOHC guys, but its great to get a good writeup for us single slammers.

I've taken out everything but the EGR because I think I need that to pass emissions where I am. the bay looks SO much cleaner. I also took out my A/C at the same time and the power steering is coming out this weekend because the lines are pretty toasted. I'd rather save the weight and have a really clean bay than pay a few hundred to get it properly repaired for the safety inspection.

I'm going to do a wire-tuck and relocate my battery to the trunk, do an E-fan conversion and a custom short ram so the filter ends up where the battery used to be. hopefully it'll look as clean as I'm imagining.

[shpaintball]

sorry thats what i meant was add it ....dont destroy theirs ...cuz your right i used his ...lol

[stlthftr1]

hey , i'm also planning to remove emissions and egr , this is the best thread i found for the single cam, can you take pictures of the whole bay?also , the two Vacuum Actuated Sensors / Switches at the back of the head .... what is their purpose. i suppose they don't affect idle or anything when inopperable.... and what about the othe V.A.S underneath the tb? any help would be appreciated since i already did a mini tuck but i want it to be cleaner and less cluttered . pm me if you don't want to reply to this thread....

[gumby74]

The two vacuum sensors at the back of the head operate the intake butterflys if I am correct. I removed those as well.The only vacuum lines I have on the head are for the FPR, and the PCV valve.As far as the remaining vacuum nipples, they can be removed with Vise Grips and filled/welded shut, you can loop them together with tubing (kinda defeats the purpose), or use simple vacuum plugs.I went as far as to source another intake manifold and perform the strip down on that piece, then I just swapped manifolds over a weekend.

[stlthftr1]

ok, thanks . well i went ahead and did this yesterday with no adverse effects that i know of yet. next is the egr. i've also seen the ka manifolds and valve covers from the truck and the fwd ones. they look cleaner would it be possible to swap them? do you have any ideas on wire tucking and making the engine look really uncluttered and clean? can you point me to some sohc posts with some relevance ? i'd appreciate it.

[spindrift187]

I actually just capped off those 2 lines on the intake mani:[IMG]https://forum-attachments.sfo2.digital ... 8.jpg[/IMG]A clearer pic of the FPR line you spoke of:I just removed/shaved off the metal hard lines:Blocked off the EGR/butterfly ports:And did the full wiretuck:

Car idles/pulls great! Switched out chassis from fastback to coupe which is why the engine bay is black in some pics in red in others(red being the car it's in now)

All in all removed the vaccuum lines/EGR/AIV/power steering/Air conditioning/clutch fan and relocated the fuse box

[spindrift187]

I actualy just capped off the 2 ports on the intake mani you looped:

[KA24Power]

have you had any issues with the coolant harlines that you capped that run under the TB? I ripped some of the hoses thinking they were vacuum lines and now I am considering blocking them off so I don't have to run new hoses.

[stlthftr1]

this is kinda what mine looks like now. these pictures still show the vacuum lines and egr misc. though . When i took of all the vacuum lines off i took out the steel lines next to the intake manifold. however i replaced the coolant line with clear nylon tubing. i might take more pix later. Any more tips on wire tucking on the sohc?also can i plug or use a small filter on the hose that runs from the valve cover to the intake tubing?


Modified by stlthftr1 at 10:05 AM 12/3/2007

[spindrift187]

have you had any issues with the coolant harlines that you capped that run under the TB? I ripped some of the hoses thinking they were vacuum lines and now I am considering blocking them off so I don't have to run new hoses.

If you are talking about the one directly underneath the TPS sensor then no since that doesnt have any coolant running through it. But the one underneath the intake mani was dripping a little after I first finished it so I put a rubber hose on it and ran a bolt in it. Then put a hose clamp on it. No issues since.

As far as wire tucking goes, patience and a soldering gun/heat shrink tubing. It's so worth it in the end. Im actually gonna re-do my harness soon for a factory look.

[KA24Power]

cool man, thanks for the advice. One more question though.. The big vacuum line that runs from the intake piping and goes back towards the EGR - did you remove all the stuff that pulls vacuum off that line rendering it pointless, or is it plumbed into your intake?

[kings88]

i got a bit ahead of myself before i saw this thread i was following the KA24DE emissions removal how to. Instead of figuring out the vacuum lines first i started removing all the emissions parts. All i have left is the FPR (i believe). I noticed y'all still have the air regulator attached on the side of the TB. According to the write up i saw that could be removed as well??

To make a long story short, i blocked off all parts that i removed so i'm pretty sure it should be ok. In any case, the car will crank but won't stay on. I got it on for about 5 seconds or so. Also the pipe that is attached to the exhaust is open. Does that need to be sealed off too for the engine to stay on? I wouldn't think so seeing as it's after the O2 sensor. Is it just a vacuum leak you guys think i'm dealing with or could it be something else?

Thanks for the help.

[KA24Power]

The pipe that runs behind the engine and connects to the exhaust is the EGR. you have to hook it up or plug it to make the car run properly. And if your car isn't running after removing emissions I'd guess vacuum leak.. whoops!

Check that everything is plugged properly or hooked up if it needs to be. Also make sure you didn't accidentally disconnect the wiring harness anywhere.

[ChrisEspo83]

hey guys im having some serious problems. i removed most of the EGR system. but i dono what to take apart when it comes to all the vacume lines right behind the valve cover. there is soo much going on back there. as of right now i am waiting for the EGR block off plate to come in from e bay. as of now for some reasion my car is spuddering and spiting the idle jumps a little then goes really low.. i have 3 vac lines open right now that were connected to the EGR control valve, i removed that and now they are all open. i tried to plug them but it makes no difference.. i have no idea where else they go and how to remove them. it seems like i have to remove the engine to get to them. anyway is there anyone in the NY area who has done this that can help me out. i will pay who ever come and helps me remove the rest of the EGR system.

thanks guys i look foward to your replys

chris

[stlthftr1]

those lines behind the head can all be removed. just take the 3 bolts holding the plate up . they're 12mm bolts btw

[ChrisEspo83]

all thoes vac lines can come out..? how.. they look like they are attached to sensors. can anyone give a picture of everything removed behind there so i can see whats going on . i really still dont get how u remove all of them and the car still runs. anyway the more help the better thanks for your reply

[stlthftr1]

yeah all those lines and sensors and even the bracket come out of there.

[anothermethod]

also can i plug or use a small filter on the hose that runs from the valve cover to the intake tubing?

I used a K&N breather.

[Space Monkey]

Hey guys, im about to swap in a DE after i rebuild it, although i was wondering with all of these lines being pulled out and sensors going, what am i losing? Can i still pass air care in Vancouver BC? and what sensors will get messed up by doing this?

Thanks.

[naspachipi]

wow wish i would of found this thread earlier..lol put new motor in and had boosted it.. spent better half of a yr tryna get the vaccume lines correct lol.... good stuff.. any one have pics of a ka24e-t with pics of what they did with the vaccume lines?

[aziankingz]

anyone have pics of each vacuum lines circled that can be removed? just the ones that will still keep the car from failing inspection.

[okinawa drift]

alright i got rid of all thata ****, including the 3 hardlines that run through the middle of the intake, but what do i do with the coolant lines under the intake? just plug them?

[jlwade]

I cannot believe I found this post. I have been vacumm leak hunting for a week. The car is a racer on a circle track so all I need is for the car to run. I was wondering just how much of this junk was needed!

Tomorrow, I start stripping lines!