Don't know where this hose goes *pic*

iMod

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I was cleaning out my spark plug galley a couple of days ago and noticed this:

p847610_1.jpg


It looks fine, but I pulled on that hose and it wasn't actually connected to anything! Does anyone know what this part is and where it connects to?
 

Supracentral

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Mar 30, 2005
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Looks like it's the vacuum reference for your fuel pressure regulator.

If it was a turbo car you'd probably have a blown motor by now. On an N/A car you are probably just running rich at idle and during decel. It will foul your cat's eventually.

Hook to any vac source on the engine side of the throttle plate.
 

Figit090

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might be. if its getting a crapload of fuel it might be causing the excessive revs. I dont know for sure though its a guess. can you feel around for where it goes? if you cannot find it and suggestions have not helped i'll look when I get to my car next.

I've never seen a "twin cam 24 valve" sticker on a 7m plenum before...interesting.

Mike - Why would that toast a turbo? just curious.
 

Supracentral

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Figit090 said:
Mike - Why would that toast a turbo? just curious.

Turbo cars have a 1:1 rising rate regulator. It adds 1 psi of fuel pressure for every pound of boost it sees from that reference line. When the line is disconnected the fuel pressure stays static.

Think about how your ECU sees this. Under normal "non boost" driving, the regulator won't get vacuum, so fuel pressure will actually be high when idling or cruising. The ECU will start to trim the fuel because it thinks the car is running too rich. Now, when you go to boost, the regulator doesn't see boost. Fuel pressure is low, however the ECU is already trimming to run the car lean. Next step = detonation & blown motor.

It's a worst case scenario. Under stock boost the chance of killing the motor is pretty slim unless you are really hammering on it. Anything above stock however and that risk goes up exponentially.

Figit090 said:
I've never seen a "twin cam 24 valve" sticker on a 7m plenum before...interesting.

Me either.. I was wondering what looked odd in his engine bay pic.
 

iMod

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The "Twin Cam 24 Valve" thing is a plate that can be unscrewed and taken off. It adds 5 hp to my car....hahahaha just kidding. The guy who owned the car before me bought a JDM engine and I've heard from other supra owners that the JDM engines came with that.

Back on topic though, I haven't been able to feel or see where that hose goes. I looked all over and couldn't see anything.
 

Supracentral

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iMod said:
Back on topic though, I haven't been able to feel or see where that hose goes. I looked all over and couldn't see anything.

At first glance it looks like all your vac hose routing is all f'ed up.

It goes here:
 

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iMod

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The vac hoses are probably all messed up and not in the right places. The guy I bought it from was a wannabe mechanic. He basically didn't know the difference between a monkey wrench and a monkey's ass. Not that I'm a mechanic, but at least when I fix things they stay fixed. He screwed up when he put in the valve cover gaskets and a bunch of other things. I've been learning slowly how to work on my Supra thanks to the people here on Supramania...basically so I can fix his screw up's.

I'll take a look at it tomorrow. It's too dark outside right now to check it out. I'll take some pics tomorrow if it's not raining for you guys to see. Then if you wouldn't mind you could let me know if my vac hose routing is ok or bad. That way I can fix it.
 

Figit090

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Supracentral said:
........Fuel pressure is low, however the ECU is already trimming to run the car lean. Next step = detonation & blown motor.
It's a worst case scenario......

thanks :icon_bigg
 

AJ'S 88NA

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Jul 26, 2007
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Most times there is a vacume hose routing sticker on the underside of the hood. Mine is still there, if not there is still the TSRM.
 

iMod

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yea I did a search and managed to find a thread where a guy posted the vacuum hose diagrams. they were pretty clear so I have a good idea now of where the hoses go. :)
 

iMod

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Okay I got everything going and my car is running again. I got the hoses sorted out and everything. There's one hose though that I have and I can't find it's home. I found this diagram on supramania disregard the blue, red, and green, that's not my markings. Everything in yellow is what I'm concerned with. I'm left with the yellow hose on the left. I can't find where it goes. I know I'll probably find it sooner or later.


p853202_1.jpg



The big question I have though is what do all those do and how crucial are they? I went about half a mile to the Texaco to get some gas, but I don't wanna drive it again until I find out if it'll ruin anything.

PS. I have my exhaust all taken off cos my friends and I were wondering if that was the problem. It wasn't but we still haven't gotten around to putting it back on. That car is so LOUD. It sounds AWESOME, not all tinny and ricy. It sounds like it wants to eat up ricy little Honda's for breakfast hahaha.


EDIT: I forgot to post the diagram lol.
 
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AJ'S 88NA

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iMod said:
Okay I got everything going and my car is running again. I got the hoses sorted out and everything. There's one hose though that I have and I can't find it's home. I found this diagram on supramania disregard the blue, red, and green, that's not my markings. Everything in yellow is what I'm concerned with. I'm left with the yellow hose on the left. I can't find where it goes. I know I'll probably find it sooner or later.


[thumb]http://img.photobucket.com/albums/v633/DarkSaiyanWarrior/missinghose.jpg[/thumb]


The big question I have though is what do all those do and how crucial are they? I went about half a mile to the Texaco to get some gas, but I don't wanna drive it again until I find out if it'll ruin anything.

PS. I have my exhaust all taken off cos my friends and I were wondering if that was the problem. It wasn't but we still haven't gotten around to putting it back on. That car is so LOUD. It sounds AWESOME, not all tinny and ricy. It sounds like it wants to eat up ricy little Honda's for breakfast hahaha.


EDIT: I forgot to post the diagram lol.
Do you have the VSV and the canister? They control the ACIS
 

iMod

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I think I found the canister down there yesterday (by feeling around cos I couldn't see anything), but I couldn't find the nipples on it. So it's making me wonder if I found the wrong canister.

Could you define ACIS please?
 

suprarx7nut

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Acoustic Controlled Induction System.

It consists of a simple butterfly valve (just like your throttle body) underneath that twin can 24 valve sticker you have. You can unscrew that rectangular plate and view into the intake and this valve.

Its purpose, as I understand it is to allow for the adjustment between short and long "runners", or channels of intake air flow.

When you're at lower rpms, the air can be mixed in the plenum with negligible effects. Once you hit about 4200 rpms, the ACIS kicks in and closes the butterfly valve which now creates two long channels of air, each of which feeds 3 pipes for the intake(sorry dont know the name of each pipe :dunce: ).

***Now here's where I'm hypothesizing***
The way i figure, when one of your cylinder's intake valves close, it causes a rush of air. The air has nowhere to go for a split second. This creates an area of high pressure. When the air is divided and kept in two sections with the ACIS, this pressure increase is notable every time a valve closes. I'm picturing that if the valve weren't there the air would not pressurize as much because it has so much more space to work with. When the next valve opens, the pressurized air is sucked/pushed into the cylinder. This results in slightly more air being pulled into the cylinder.

And woolah! You get a *tiny* little extra power..... supposedly.


***end of my idea*** (experts please weigh in if I was off anywhere :))

Every now and then i can notice my engine pep up just a slight bit @ ~4200 rpm, but it doesn't seem to make any sort of difference on the highway in 3rd gear past 4000rpm. Really just 1st and 2nd gear.


Hope that helps and I hope *most* of my hypothesis was right. My fluid dynamics teacher is horrible though, so if its wrong, i blame it on her ;)
 

iMod

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oh I see, thanks for the explanation.

Now with that yellow hose (on the diagram) unplugged from the tank, is it gonna break anything or blow anything up?