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Cleaning up TB vac lines on 6 bolt swap

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endeffect0

15+ Year Contributor
544
2
Sep 19, 2006
Lancaster Area, Pennsylvania
I am sick of fighting with a bunch of little boost leak issues with all the factory vac lines on and around the Throttle body. I have a six bolt swap, with head, mani, and TB. I do not need to retain any of the emissions stuff.
what, If anything can I not cap off.

Just to save the trouble I am still searching for info on this in other threads, And i do have dsm link (v2) for those who wont look at the car bio.
 
Actually you wan't to keep the fuel pressure solenoid connected otherwise you will have problems starting your car after a long drive, do not remove it! Cap everything off or run a hose from one port on the TB not used to another port not used, same as capping it. Get a blockoff plate for your TB as well that keeps the ISC and if you have a boost guage T it in the line somewhere that runs from the fuel solenoid to the intake manifold.
 
^I've been running without an FPS for a long time and don't have any issues.


I also have a 1g in a 2g.

As far as I can remember, the only vacuum lines I have on are as follows:
-bov to intake manifold
-mbc to wastegate
-mbc to intake manifold
-valve cover breather to catch can to intake pipe
-PCV valve to check valve to catch can to intake manifold
-AFPR to intake manifold
-brake booster to intake manifold

The EGR system, EGR and EVAP solenoids, and charcoal canister and associated items (NOT including the line to the gas tank - that needs to be left in and vented to the atmosphere) are all removed. I am able to remove the solenoids since I have DSMlink. I have my boost gauge teed into the vacuum line from the AFPR to the intake manifold.

I'm using a JDM Galant 1 nipple throttle body, which I have pulled and had the hole welded shut. You can also tap the hole(s) and install a set screw to block them off if you want a cleaner look than looping lines or putting on vacuum caps.
 
I am also FP solenoid less with no issues at all. Wouldn't have posted it if it wasn't fine to do.
 
Someone on DSMtalk was having problems after driving long distances and a member said if you don't have the solenoid connected the car can't tell what the fuel temp/pressure is or something along those lines and it will have difficulty starting right away and you have to let it sit for a while before it starts again. What's the advantages of removing it? I thought DSMlink only gets rid of the check engine error code when you remove the solenoid in a 2g, nothing else.
 
I've got a question along these same lines. I removed all my vac lines right when I got the car, but I have to keep replacing the rubber covers I put on them. How tight are they supposed to be?
I am using ones that are a super snug fit, then I zip-tie them down, but should I be using some that are pretty easy to slide on (but not super loose) and zip those down? I'm just tired of replacing them every like, 200 miles because they just keep cracking and the tops break off...
 
Yea, the thing about the caps is they do crack and get brittle on the outside but I think they will still hold vacuum for the most part. Use actual vacuum line on the TB ports that are open and run the ports to each other, saves you 4 caps and the line lasts alot longer.
 
just cut a piece of a line stuff a screw in there.works for me

Yeah it works. But if something looks bad, thats just as bad as if its not functioning properly.

Yank the ports out and have them welded shut if you really want it to look good and you never want to deal with it again.

And the FPS is useless, along with all the other solenoids up on the firewall. Disconnect lines on them, leave them plugged in to keep from throwing a CEL, and tuck them away out of sight.
 
Am I the only person who thinks the FPS isin't useless? It has a purpose and there is no gain in removing it other then the back wall of the engine bay looks cleaner because there aren't any solenoids. It's almost like saying I'm gonna put a big ricer wing on the back of my car because it looks better when in reality it will do little to nothing for you.
 
I guess if you are showing you car you wan't the engine bay to be clutter free, that's why people reroute their battery. The tail was a bad comparrison but it makes a little sense when someone is putting it on a stock chevy caviler or honda, am I right? All I know is I'm leaving my FPS connected.

Here is the dsmtalk post I found about removing the FPS, here is why dude said. Basically, without the fuel pressure solenoid, the car has no way of automatically richening up the air/fuel ratio on hot starts.
When the solenoid is installed and functioning correctly, it bumps up the fuel pressure on hot starts http://www.dsmtalk.com/forums/showthread.php?t=227097
 
I guess if you are showing you car you wan't the engine bay to be clutter free, that's why people reroute their battery. The tail was a bad comparrison but it makes a little sense when someone is putting it on a stock chevy caviler or honda, am I right? All I know is I'm leaving my FPS connected.

Here is the dsmtalk post I found about removing the FPS, here is why dude said. Basically, without the fuel pressure solenoid, the car has no way of automatically richening up the air/fuel ratio on hot starts.
When the solenoid is installed and functioning correctly, it bumps up the fuel pressure on hot starts Runs rough after sitting warm/hot for a while - DSM Forums: Mitsubishi Eclipse, Plymouth Laser, and Eagle Talon Forum: DSMtalk.com

Well, it's possible that different cars are going to be effected differently when things are removed or added. But I'm saying that a good majority of the time, every DSM that I have seen with the FPS removed, has no problems because of it. You can easily test it out on your car and see if it effects anything...if it doesn't, take it out, if it does just hook the lines back up. No big deal.

I removed mine a long time ago, I've never had a single problem, ever.
 
Thanks for all the advice and links. I will be cracking into this the first day I am off. and probably even post some before and after pics as a thank you.

On the running a FPS or not. Please realize the whole point of this exercise is Not to clean up my under hood. I could care less what it all looks like, I do care how it all works however. Eliminating unnecessary vacuum lines reduces the potential for a leak by 3* for each section of hose. (each intersection as well as the hose itself all are potential failure points.) now that might not be real probability math.. but the less potential for failure the better.

ill read up on those link and post if i have any questions or bright ideas.
 
Just to finish off this thread.

As far as boost leaks I can now hold 25 psi for 45 seconds and 20 psi till I get bored. This is up from 15psi dropping to 12 in 30 seconds. I was previously unable to find the leak points behind the manifold because of all the possible leak points and lack of access to the locations. after the fact i found i had one leak at the tb, and that was an easy fix.
This gave me the confidence to turn up the boost to 22 psi and it all seems to be holding together just peachy.

On the Fuel Pressure Solenoid. I initially noticed no difference when temps were above 70*, now that temps are low in the mornings its really obvious. Maybe it has to do with my fuel setup, wally 255lp & 880 injectors, but either way it never starts first crank when its cold out. its usually the second sometimes the third try that it catches on. last winter it always started on the first crank. Does that bother me in the least. No. I always warm up my car so its not like i am sitting in the driveway for any longer than normal. there is never any risk of it not starting, it aways does. So I am not bothered by it in the least, but it needs to be said on my setup there is no question of the difference.

Somewhere i have a picture of all the emissions junk and removed vacuum lines I will try to dig it up and post it.
 
On the Fuel Pressure Solenoid. I initially noticed no difference when temps were above 70*, now that temps are low in the mornings its really obvious. Maybe it has to do with my fuel setup, wally 255lp & 880 injectors, but either way it never starts first crank when its cold out. its usually the second sometimes the third try that it catches on. last winter it always started on the first crank. Does that bother me in the least. No. I always warm up my car so its not like i am sitting in the driveway for any longer than normal. there is never any risk of it not starting, it aways does. So I am not bothered by it in the least, but it needs to be said on my setup there is no question of the difference.

My understanding is that the FPS helps to start the car when it's hot but you are saying the opposite. From what you are saying I don't think that the hard starts can definitively be associated to the lack of a FPS. If you still have the solenoid it would be super easy to hook it back up just for testing purposes and see if it makes any difference.:)
 
My understanding is that the FPS helps to start the car when it's hot but you are saying the opposite. From what you are saying I don't think that the hard starts can definitively be associated to the lack of a FPS. If you still have the solenoid it would be super easy to hook it back up just for testing purposes and see if it makes any difference.:)

Interesting...
there is no question that my car is more difficult to cold start this winter than it was to start on the previous one.
Much has changed since last winter; injectors, fuel pump, fuel lines, intake system, ignition system... not to mention my tune. suffice it to say the FPS is only one of the many things that may have influence.
I will hook back up the solenoid just for curiosities sake, seems doubtful now that it will make the difference.


Just to clarify, Hot start has Not suffered in the least. not even when its a hot day and enginebay temps are such that you don't want to rest your hand on the hood. :thumb:
 
I am stuck on my 6 bolt swap need help with the vacuum lines and what not. I am deleting emissions just need help or a good diagram on what to do. If I looked up a diagram do I look up 1g or 2g since its a 2g car but a 1g motor so lost car is just sitting in my garage waiting to be started up please any help is appreciated
 
I am stuck on my 6 bolt swap need help with the vacuum lines and what not. I am deleting emissions just need help or a good diagram on what to do. If I looked up a diagram do I look up 1g or 2g since its a 2g car but a 1g motor so lost car is just sitting in my garage waiting to be started up please any help is appreciated

Hate to bump, but I'd love the answer to this question right now. Thanks!
Edit: i skipped right over the first post which answers this. Sorry for bump
 
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