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Vacuum Delete Clarification

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PFC_CiarlilloM

10+ Year Contributor
234
0
May 22, 2011
Euclid, Ohio
Okay, so, I am in the process of redoing my head gasket, and like a mad man I ripped the vacuum lines off of the back of the intake manifold without really looking at everything to see where each hose went. Now, I can't really follow the OEM diagram to connect each line correctly for some reason, but to my understanding those lines are for emissions, and aren't really needed.

I guess what better time to do the vacuum delete then now? Anyways, I just wanted to clarify/verify that I can pull EVERY vacuum line, and only run the vacuum lines in this picture that I attached.

Sorry to beat on a dead horse, but just wanted to be safe than sorry.

More info;
1996 (Auto) Eclipse GSX
Glowshift Digital Boost/ Oil Pressure Gauges
NXS MBC (Stainless Steel revision)
 

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i personally think that tapping into the FPR line for your boost gauge is a bad idea, id tap it into your BOV vacuum.

tapping into your bov line is an even worse idea.

if you pull all the vacuum lines then you have open ports to connect your boost gauge to, no need to tee into anything.
 
Thanks for the quick reply guys!

@urbansmoker1- Why do you say that it's a bad idea to tap into the FPR?

I'll just pull all the lines (leaving all emission still plugged in), cap everything not used, and try seeing if attaching the boost gauge to the "P" port makes for a cleaner look.
 
i personally think that tapping into the FPR line for your boost gauge is a bad idea, id tap it into your BOV vacuum. other then that everything looks fine to me.

It worked great for me. I just finished doing a vaccum delete on my car last night. :thumb: Theres alot of people that are for it and there are just as many against it. I see no problem as I have done this in past cars just fine with no problem. It will get a more accurate reading from the fpr vs. the bov.
 
why not just run it from its own source so there is less of a chance of one negatively affecting the other. i know every fpr i have ever installed specifically said to give it a dedicated line same with a wastegate or bov
 
if your tapping into the FPR vacuum you can change the pressure ratio getting to the regulator and you can have an off base fuel pressure. since its something as important as fuel, i decide to leave it alone. What is your reasoning behind the BOV being a WORSE idea? I most likely will tap into where my PCV used to be at this point.. pending you can give me a reason behind why the BOV is a bad idea, i have not had one issue with it staying closed during boost, or open during idle.
 
This is a little off topic here, but am I able to just disconnect the thick A/C hose running from the compressor to the front of the engine bay on the timing side? My A/C doesn't work, and I would like to clean up the bay a little bit.

(I boxed-highlighted in the attached picture of the hose I am referring to)

*Also note that this is a googled image, and not my actual bay*
 

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One thing that I don't see in the picture that you have there is the VCV hose that runs from your valve cover to your intake pipe. I would not cap that off. If you are worried about oil coming from there just get a good catch can installed or just leave it as is.

You probably already thought of this but I didn't see it in your diagram so I just wanted to point it out. Technically I think that is classified as a vacuum line.
 
One thing that I don't see in the picture that you have there is the VCV hose that runs from your valve cover to your intake pipe. I would not cap that off. If you are worried about oil coming from there just get a good catch can installed or just leave it as is.

You probably already thought of this but I didn't see it in your diagram so I just wanted to point it out. Technically I think that is classified as a vacuum line.

He said that it's just an image he pulled off the internet, not his engine.
 
Okay, so, I am in the process of redoing my head gasket, and like a mad man I ripped the vacuum lines off of the back of the intake manifold without really looking at everything to see where each hose went. Now, I can't really follow the OEM diagram to connect each line correctly for some reason, but to my understanding those lines are for emissions, and aren't really needed.

I guess what better time to do the vacuum delete then now? Anyways, I just wanted to clarify/verify that I can pull EVERY vacuum line, and only run the vacuum lines in this picture that I attached.

Sorry to beat on a dead horse, but just wanted to be safe than sorry.

More info;
1996 (Auto) Eclipse GSX
Glowshift Digital Boost/ Oil Pressure Gauges
NXS MBC (Stainless Steel revision)

Everything except the lines dealing with the PCV system and brake booster.
 
you can do what you want but the more outputs sharing the same source for a signal will cause fluctuations in function even if they are so small that you cant notice.

plus usually you want a boost pressure source for a pressure gauge after the throttle body so you can see the actual pressure of the incoming air. the blow off valve is far enough away from the im that its reading can be different enough to actually show on a gauge. try your gauge in both spots and see. its why map sensors are to be taped into the manifold so its a true pressure reading after the tb so its the most accurate spot for proper monitoring and tuning.

there are so many taps off the im why run a line to the bov for the boost pressure source.

if you dont think it will matter then put all your sources that need vacuum/boost on one line with a million tees.

this is like one of the should i put an inline filter before the bov or other sensor question. personally i always do. many people will say no need but its to protect the expensive bits in the long haul.
 
If you run your boost gauge off of the bov line it will not be the most accurate reading. But yeah the safest place to run your boost gauge is off the "P" on the Throttle body. One less port to plug and one less vaccum tee to deal with. And if your looking for a cleaner engine bay block off the EGR, loop your coolant lines that normally run hot coolant through the throttle body, install a FIAV bypass plate or look up how to delete it for free, and take out the big charcoal canister beneath the battery tray support bracket.
 
If you run your boost gauge off of the bov line it will not be the most accurate reading. But yeah the safest place to run your boost gauge is off the "P" on the Throttle body. One less port to plug and one less vaccum tee to deal with. And if your looking for a cleaner engine bay block off the EGR, loop your coolant lines that normally run hot coolant through the throttle body, install a FIAV bypass plate or look up how to delete it for free, and take out the big charcoal canister beneath the battery tray support bracket.

+1 to this.

Run the boost gauge from the P source. If you decide to remove the charcoal canister, I would suggest extending the line with a hose to somewhere outside the engine bay. A hot gas tank can generate a lot of fumes and I'd hate to see that cause a flash fire. :|
 
So I just took care of the vacuum lines running behind the intake manifold, and capped them all off. All I have to do now is just cap their ports off on the intake manifold itself. I am going to be running my boost gauge off the "P" port on the throttle body. I also decided to keep the FPS for now incase for some reason that I can't upgrade my fuel pump before winter. I read that it helps w/ cold starts. I think that's everything, right?

Also can someone tell me what the connectors I highlighted in the red box are? They were like that ever since I got the car, and can't seem to find them on a diagram.

*On a side note, I think I know why my A/C wasn't working, besides having a shitty gatorback belt, there wasn't any freon in the lines LOL. Well I guess if I want A/C I will just have to install the pulley, belt, put the hose back on, and try putting some freon in it.
 

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@tay97gst Those are them alright. Thanks for the help, I am sure I'll be using that thread a lot while putting the car back together. I'm assuming that the P.O. soldered the blue engine speed detection connector wires because my car atleast started, but you know what they say about assuming things LOL
 
Quick question, I capped off all of my emissions but left the solonoids plugged in as I have no way to tune yet and don't don't want any CEL's. My question is can I get rid of that thicker hose that runs into my air intake hardpipe? It seems as if it runs into the EGR solonoid. I don't have my manual w/ me and forgot exactly what that can is called.

*Its the blue hose that's in my second pic*
 
Quick question, I capped off all of my emissions but left the solonoids plugged in as I have no way to tune yet and don't don't want any CEL's. My question is can I get rid of that thicker hose that runs into my air intake hardpipe? It seems as if it runs into the EGR solonoid. I don't have my manual w/ me and forgot exactly what that can is called.

*Its the blue hose that's in my second pic*

If you are deleting emissions then yes you can remove the hose and canister. Just retain the check valve that goes to the breather for the gas tank.
 
If you are deleting emissions then yes you can remove the hose and canister. Just retain the check valve that goes to the breather for the gas tank.

my breather has a hose i put on it when i deleted my emissions, which way would you have the check valve? so air can escape the tank but not enter? im gonna pick one of these up because ive just been venting the hose to the ground, probably loosing so much gas in vapor on hot days due to that though.
 
@NeMiZiS - I apparently never had any in my lines because I went straight into tearing it down w/ out even thinking about releasing it. Pretty much your mistake... I am guessing that's why my A/C never worked haha. I probably should have tried adding some freon, but it's too late now LOL. Atleast I know the problem most likely. I could only imagine being there when you did it.

@LiquidX - I think I may have the incorrect terms, what is the black solonoid called? (Picture #2; w/ the two caps, and blue hose) I capped off all the lines on the EGR (It's attached to the Intake Manifold, correct?)

I will post some pictures up, and a more detailed description of my vacuum setup after I tackle this timing job or more like battle of tensioning it correctly (First major tear down as head gasket went, and first timing job)
 
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