what vacuum nipples can be plugged on this upper intake? (pictures)
09-07-02, 12:17 PM
#1
what vacuum nipples can be plugged on this upper intake? (pictures)
i took my upper intake off to find the last of the vacuum leaks once and for all... which vacuum nipples can i plug (i have no emissions.) i just want to get the damn hoses out of there. this picture is the set of 4 vacuum nipples closer to the drivers side.
09-07-02, 01:38 PM
#5
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Well, in the first picture, keep the big one because it feeds from the front of the throttle plates (no vacuum) and is for the oil injectors. The one above it is fed from the front of the throttle plates(no vacuum) and should feed the fuel injector air bleeds. That nipple is b/t two OIL injectors on the intake manifold. I'd keep it, but others have capped the nipple b/t the oil injectors and the one on the throttle body.
Cap the very top one. Its of no known use.
The very bottom one is the only one that really pulls a vacuum, and was for the water thermo valve just to the left of it . You can cap that if you want. It feeds the double throttle diaphram on the front of the throttle body. You won't really miss it.
I'm not well versed on the front three. At least one feeds a vacuum to the solenoids so they can work. I'd keep those three. You need a vacuum source for the green solenoid which is the switching actuator on the turbo.
Cap the very top one. Its of no known use.
The very bottom one is the only one that really pulls a vacuum, and was for the water thermo valve just to the left of it . You can cap that if you want. It feeds the double throttle diaphram on the front of the throttle body. You won't really miss it.
I'm not well versed on the front three. At least one feeds a vacuum to the solenoids so they can work. I'd keep those three. You need a vacuum source for the green solenoid which is the switching actuator on the turbo.
09-07-02, 01:59 PM
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1. cap it off
4. Cap it off
2. Keep it and run it to the nipple b/t the two OIL injectors.
3. Keep it and run it to the oil injector spider. If you premix, cap it off along with the top of the oil injectors.
The three on the front of the throttle body I'll have to think about for a bit. I'll have to go out and look at my spare engine. Long walk.
4. Cap it off
2. Keep it and run it to the nipple b/t the two OIL injectors.
3. Keep it and run it to the oil injector spider. If you premix, cap it off along with the top of the oil injectors.
The three on the front of the throttle body I'll have to think about for a bit. I'll have to go out and look at my spare engine. Long walk.
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09-07-02, 02:33 PM
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In the second picture with three nipples.
1. Number one Feeds real vacuum to the green, grey, and yellow solenoids.
2. Number two feeds the pvc.
3. Number three feeds/sucks whatever the pvc also.
One thing is certain. The pressure regulating valve on the secondary fuel rails rear end. MUST have a manifold pressure going to it at all times! You could run the front top nipple on the throttle body straight to it. If the fpr does not see boost pressure, it ain't gonna regulate correctly. Lean running causes kabooom! rattle, rattle, tow truck.
1. Number one Feeds real vacuum to the green, grey, and yellow solenoids.
2. Number two feeds the pvc.
3. Number three feeds/sucks whatever the pvc also.
One thing is certain. The pressure regulating valve on the secondary fuel rails rear end. MUST have a manifold pressure going to it at all times! You could run the front top nipple on the throttle body straight to it. If the fpr does not see boost pressure, it ain't gonna regulate correctly. Lean running causes kabooom! rattle, rattle, tow truck.
Last edited by HAILERS; 09-07-02 at 02:37 PM.
09-07-02, 02:42 PM
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Read my edit to my post above this one. I'd run the top one to the prv on the back of the secondary fuel rail.
I call it a pvc but it has another name. Purge valve???? That large black plastic thing just inboard and aft of the oil fill pipe. Sucks fumes out of several places like the *crank case* and ??????? I'm really not well versed on the purge valve. Cap it off I say! Both second and third nipples on the front. Later today I'll look at the fuel section towards the rear and see what the routing is to around, and from the purge valve. I wouldn't worry, just cap them.
I call it a pvc but it has another name. Purge valve???? That large black plastic thing just inboard and aft of the oil fill pipe. Sucks fumes out of several places like the *crank case* and ??????? I'm really not well versed on the purge valve. Cap it off I say! Both second and third nipples on the front. Later today I'll look at the fuel section towards the rear and see what the routing is to around, and from the purge valve. I wouldn't worry, just cap them.
09-07-02, 04:05 PM
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I came back and read my last post. Even confused me. In the first paragraph I was refering to the pressure regulating valve on the back of the secondary fuel rail. And running a vac hose from the top, #1, nipple on the front of the throttle body, to the pressure regulating valve.
Second paragraph was talking about the bottom two nipples on the front of the throttle body, that go to the purge valve.
I don't think I confused you, but what if...
So, just why do you think you have a vacuum leak???
Second paragraph was talking about the bottom two nipples on the front of the throttle body, that go to the purge valve.
I don't think I confused you, but what if...
So, just why do you think you have a vacuum leak???
09-07-02, 06:55 PM
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I don't see how you get around not using the twin scroll solenoid. I know the turbo will boost without it, but I thought the switching actuator on the bottom of the turbo helped the turbo spin up sooner.
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