Vacuum Tree

Black Sun 5.0

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Mar 23, 2002
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L.I., N.Y.
So I have my car put back together, and sent it to the machanic to button-up a few things. I noticed over the weekend that the vacuum tree by the firewall is totally busted up. How involved is it to redo the vacuum lines? Also, what impact does this have on the car (performance, problems, etc.). There's a reason why I'm asking 'silly' questions, but I need confirmation of something. Thanks.
 
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If you're going to re do them ( completely replace the old lines) the only vacuum line that would cause you any grief would be the line that goes to the cruise control because it goes to the servo and that is tucked you by the drives door under the splash shield, the rest of the lines are fairly easy to reach.
With your Vacuum Tree busted up you have a vacuum leak and the problem with a vacuum leak it that when you first start the car it doesn't want to run and most times it will backfire in the intake. Once it's warmed up it seems to run fine but it always sounds l;like you have a big lopey cam in the car.
 
Other than the performance problems caused by a vacuum leak, the vacuum tree isn't anything special. It is nothing more that a piece of plastic with a bunch of places to connect stuff. All you have to do is be careful not to break anything that you don't have a replacement for close at hand.

The diagram below is for an 89 5.0 Mustang . The 86-88 5.0 Mustangs will be similar with the addition of a vacuum line from the intake manifold to the MAP sensor mounted on the firewall next to the vacuum tree.
40914d1134573254-heat-not-working-properly-89-5.0-auto-trans-ac-vacuum-diagram.gif
 
If you're going to re do them ( completely replace the old lines) the only vacuum line that would cause you any grief would be the line that goes to the cruise control because it goes to the servo and that is tucked you by the drives door under the splash shield, the rest of the lines are fairly easy to reach.
With your Vacuum Tree busted up you have a vacuum leak and the problem with a vacuum leak it that when you first start the car it doesn't want to run and most times it will backfire in the intake. Once it's warmed up it seems to run fine but it always sounds l;like you have a big lopey cam in the car.

Doesn't poor vacuum also affect other things such as breaking, idling, etc.? I think cruise control is the least of my problems right now, I can't go cruising anywhere at this point. Then again, I think it's the only thing that works on the car.
 
You can get a nice metal vac tree in the aftermarket (they are pricey) or make one from parts at the local hardware store.
 
Doesn't poor vacuum also affect other things such as breaking, idling, etc.? I think cruise control is the least of my problems right now, I can't go cruising anywhere at this point. Then again, I think it's the only thing that works on the car.

When I said run earlier I should have included and poor idling also.

With the Vacuum T busted and not being a sealed unit any components that needs vacuum will be effected so yes the brakes, HVAC, etc, will be effected by the loss of proper vacuum.
 
Sorry my misunderstanding....... I read it as
[I noticed over the weekend that the vacuum tree by the firewall is totally busted up.

Yes any cracked or disconnected vacuum line can and will cause you problems. The hard part is usually finding them.
 
You can get bulk hard lines at the parts store. I prefer to use rubber vac line (grab several feet of every size) and replace them one at a time.
 
Oh, trust me, there's no problem finding the bad lines here. :rolleyes:

If you have the leaks found you've got 80% of the battle won, now it's just a process of replacing those lines.
As suggested by HISSIN50 you can get rubber as a replacement which seem to be easier to find that the hard plastic lines , that option is up to you though.
 
Hey, any way of getting a printable version of that diagram?

Click on the diagram to make it the maximum size. Then right click anywhere in the middle of it. Select copy from the dialog box.
Go Start, Programs, Accessories and open Paint. From Paint's Edit menu select Paste. The diagram will paste onto the blank page. Do a Save As to keep the copy or select Print from Paint's File menu.
 
Another question about having NO vacuum: how does this affect fuel delivery, if at all? I get smoke that wreaks of fuel coming from my exhaust and I'm just trying to determine if it's related. It doesn't appear to be coolant or oil related and seems to increase after the car has been running a while.