Taboo speed shop vacuum diagram and removal for 1g and 2g.

I've noticed a few threads with people looking for these pictures since the website is no longer available. A wiseman suggested that I post them in a tech article so here they are. I was going to include the original text from the taboo site, but the site does not support the right click function. I put links for the archive of the site on the bottom of the page if you would like to view this text.

EDIT: The original text was sent to me by Pube Stache and I have included it in the article. I've also received a few PM's about the advantages of this mod. The primary function of this mod is to clean up the engine bay by reducing the amount of visible vacuum lines. Although the power gains from this mod are minute your car will run "cleaner" due to the lack of EGR. If you don't know what EGR is, here is a helpful link: http://www.ukcar.com/features/tech/Engine/techno/exgr.htm

EDIT No. 2: The images for the original document have gone missing so links have been added for the original diagrams. Refer to post No. 2 for the "after" diagrams. -19Eclipse90

2g Before and normal vacuum wiring:

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On account of the above picture gone missing, the '95-'97 diagram is here:

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The '98-'99 diagram is here:

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2g After:

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The WGS, FPS, EGRS and EVAPS ports don't need to be
plugged. However, leave them plugged in to prevent the ECU
from throwing CEL and plug the port of the evaporative
canister hose on the turbo inlet hose after you remove the
canister. The boost gauge may be ran off the "P"port of the
throttle body or the FPS line.

Also found the diagrams for the 1g-

1g Before and normal vacuum wiring:

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On account of the above picture gone missing, here's the 1G turbo diagrams:

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For completeness, here's the 1G 2.0L non-turbo diagrams:

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1g After (I've got 2 different pics):

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The WGS, EPS and TVV ports don't need to be plugged. However, plug the port of the evaporative canister hose on the turbo inlet hose after you remove the canister (not shown). The boost gauge may be ran off the "P" port of the throttle body or the FPS line.

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The fuel pressure solenoid can be safely removed. Its function is to increase the fuel pressure on start-up by closing the vacuum path to the fuel pressure regulator which is suppose to prevent the fuel from evaporating when the engne is hot. This is not a problem when high volume fuel pump is being used or might take just a bit more cranking in case of completely stock fuel system.

1g "Race only" set-up:

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Tabbo 2g:
http://web.archive.org/web/20040622114931/http://www.taboospeedshop.com/emissions1.htm
Tabbo 1g:
http://web.archive.org/web/20040621102025/www.taboospeedshop.com/emissions.htm

 

[19Eclipse90]

This is way past due. Despite our best efforts, people still use the above diagrams to delete their vacuum lines. Since this remains an extremely popular thread and people continue to link to it, adjustments have been made to the diagrams to illustrate the correct way to do this. Folks -- do NOT "T" into your BOV line!!! Here are the corrected vacuum elimination diagrams. It is worth mentioning that, unless you've made other arrangements, the PCV valve and brake booster line MUST remain connected to the intake manifold.

Thanks to kenamond and knochgoon24 for their respective (links below) contributions to this site which were leveraged to create the two diagrams for the bleeder styles:
http://www.dsmtuners.com/forums/151389864-post1.html
http://www.dsmtuners.com/forums/152154778-post7.html

If you want to know about the catch cans and why I did not include them in the diagrams below, it is simply because the PCV system is so well described with potential setups for different applications illustrated here: http://www.dsmtuners.com/forums/articles-engine-fuel/366890-4g63t-pcv-system.html.

FOR YOU '95-'96 GUYS -- Check out this walk-through posted by 1995-tsi-awd: 2G Walk Through How To Remove Emissions


EDIT: The '98-'99 models have a little "different" setups than earlier model 2Gs and have been a source of confusion for many people. Diagram "A" below is the original diagram for those vehicles. Diagram "B" is the vacuum reduction version. Items marked with blue can be completely removed from the vehicle, which would also include - on AWD models - the hard lines outlining the passenger side of the engine bay running to the charcoal canister.

Also, there are a number of people who suggest keeping the check valve installed and using a piece of hose to route it outside the engine bay or underneath the vehicle. It is up to you if you want to do that as cars have been run both ways without issue.

1G Diagrams - Refer to Post #1 for original diagrams

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2G Diagrams - Refer to Post #1 for original diagrams

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98-99 Diagrams
w/ and w/o (respectively)

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[XC92]

Sorry to be reviving an old thread but the above chart is different for '92 Turbo DSMs as I just found out while replacing all the vacuum hoses on my '92 Talon Tsi. Here's a link to the correct chart for that year:

https://www.dsmtuners.com/threads/list-of-all-vacuum-hoses-for-all-dsm-models-where-used-sizes-lengths.544558/post-153893965

From what I can tell the difference is that the order of hoses connected to the throttle body are reversed between '88-'91 and '92, and the color of some of the hoses are different. Not sure if the former ultimately matters but I think it's useful to know so that at the very least you don't waste time scratching your head wondering why some hoses are flipped on your 1Gb. But it would matter if each pipe has a different vacuum level.

 

[19Eclipse90]

Unlike on the 2G since the nipples are actually labeled on the diagram for those, order of presentation on the 1G diagrams does not necessarily equate to physical location on the throttle body in the car.

There are (3) different part numbers for 1G turbo throttle bodies, retrieved from ASA. They relate to model years:

1990: MD129143​

1991-1992: MD166235​

1993-1994: MD191206​

Consider the 1990 throttle body which has two nipples on the top and two nipples on the front (radiator side) and tell me which port is which based on its diagram:

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Compare the 1990 diagram to the 1991 diagram and you'll determine that they are 100% identical in every way but the 1991 may be presented slightly neater (front of vehicle at bottom of diagram rather than at top). We know from ASA that the 1991 model received a newly designed throttle body, one that has four ports on top:

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​

Keep in mind, the 1990 and 1991 vacuum systems are identical. Now refer to this thread where we determined the identity of at least one nipple on the 1990 throttle body: 1G - confirm 90 TB ports. It does not necessarily "align" with the 1990 diagram.

In the 1991 and 1992 FSM, it can be found that the nipple labeled "P" on the throttle body is for the "purge hose".

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That means the P-port is RED. As you are probably determining, that aligns with the position shown in the 1992 diagram but not the 1991. Maybe that is why Mitsubishi revised the 1992 diagram. The 1991 and 1992 models use the exact same throttle body. And aside from the not 100% matching positions of these hoses on a diagram that may not have initially intended to show exact positions anyway, it can be observed that the 1991 and 1992 systems are functionally the same. Thereby we know that 1990-1992 emissions systems are functionally the same; 1991-1992 are physically and functionally identical.

In 1993, the P-port was moved from the plenum side of the throttle plate to the intercooler side like every other port. I touched on this before at least once in Vacuum diagram for a 1g in a 2g. You can review the specifics here:

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[XC92]

So I should ignore where the diagrams show each throttle vacuum port's physical position and just go with functional "position"? If so then P is easy, being Purge. E is Evap, but via the thermo valve and not directly. But what about A1 and A2, which don't suggest any subsystem?

I actually took lots of photos before I removed everything so I know what connects to what. I just want to confirm that it was connected properly before, all the more so because the main reason for this overhaul, aside from its being a 31 year old car that probably stood to benefit from it, was a rough idle that often died unless I carefully feathered the clutch to avoid overloading the engine. I want to make sure I connect everything right.

Probably not the right thread to answer this, but since we're here might as well, what connects to A1 and what to A2? I've never seen most of the above diagrams and I own the '92 physical FSM and not just the PDF everyone's going off of which only covers up to '91 models.

 

[19Eclipse90]

E is for EGR, actually.

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Again, the 1992 diagram may have been revised to actually show physical locations. Functionally, it won’t matter. But from what evidence I have on-hand, it does appear to suggest that 1992+ diagram shows actual locations - that is, A2 is black, A1 is yellow, E is green, and P is red.

Do your records / pictures match the 1992 diagram?

 

[XC92]

E is for EGR, actually.

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Again, the 1992 diagram may have been revised to actually show physical locations. Functionally, it won’t matter. But from what evidence I have on-hand, it does appear to suggest that 1992+ diagram shows actual locations - that is, A2 is black, A1 is yellow, E is green, and P is red.

Do your records / pictures match the 1992 diagram?

Yeah, I meant to type EGR, not Evap (that being purge of course). And, the way mine was set up prior to my removing all the hoses was (from rear to front):

A2: Black, connected to side nipple of purge valve & rear nipple of PCSV via splitter

A1: Yellow, connected to outer nipple of thermo valve & side nipple of EGR valve via splitter

E: Green, connected to inner nipple of thermo valve & top nipple of EGR valve via splitter

P: Red, connected to front nipple of purge valve & front nipple of PCSV via splitter

I.e. per this:

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Or this:

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I've also been testing every valve or solenoid that I've removed, and everything checks out. The only part that's bad is the O2 sensor which had no continuity between terminals 3 & 4, so I ordered a new Denso from RockAuto. Should arrive tomorrow and hopefully everything else is ok.

It may well have been the main cause of my rough idle and poor mpg, although I'm sure that there were other things at play like small boost leaks (4 of 9 exhaust manifold studs were broken), dirty throttle and valves, etc.

I also have all new gaskets, o-rings, hoses, clamps, etc., and did a thorough job cleaning everything, with a fresh coat of KBS for good measure. Hopefully the car will run like new when everything's back on.

 

[19Eclipse90]

Sounds sorted to me.

For most people, this won’t matter at all but for those truly going for OEM appearance, it’ll be nice not having to run through all that.

 

[XC92]

Sounds sorted to me.

For most people, this won’t matter at all but for those truly going for OEM appearance, it’ll be nice not having to run through all that.

I'm now reinstalling all the vacuum hoses I removed and noticed that the purge valve vacuum splitter has one port with a white stripe by it that appears to be constricted, or is perhaps a check valve. Blowing into it is much harder than with the other 2 ports.

It's the port that connects to the throttle "P" port. Do you know anything about this?

I just posted a thread about this here:

https://www.dsmtuners.com/threads/2-quick-intake-exhaust-questions.544652/