What is this vacuum line for? 1993 Ford explorer | Ford Explorer - Ford Ranger Forums - Serious Explorations
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RADIOACTIVE_TOOL_SHED___

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What does this vacuum line do? The explorer has horrible take off and idles rough and I can hear the vacuum leak inside of the truck can anyone please send me a link to a new vacuum hose for it? Thank you

20201129_181129.jpg
 



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Orrsa

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Hi Did you get a response? My 93 just started a rough high idle and a air leak . What and where is the picture ?
Thanks Scott
 






ChildIdenticant

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That one is probably just supposed to be capped off, but with an actual rubber cap.
Not all the ports are used, at least on mine. Unless you take a zoomed out photo, couldn't tell you what goes to what for sure. but the vacuum circuit branches are:
cruise control, auto trans, fuel pressure reg, havac , bimetal valve@ air intake, brake booster ... I think that is it.
 






Orrsa

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That one is probably just supposed to be capped off, but with an actual rubber cap.
Not all the ports are used, at least on mine. Unless you take a zoomed out photo, couldn't tell you what goes to what for sure. but the vacuum circuit branches are:
cruise control, auto trans, fuel pressure reg, havac , bimetal valve@ air intake, brake booster ... I think that is it.
I did find a rubber cap on the garage floo but could not locate
Where this cap went. Any ideas on where to look? Thx Scott
 






CDW6212R

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What does this vacuum line do? The explorer has horrible take off and idles rough and I can hear the vacuum leak inside of the truck can anyone please send me a link to a new vacuum hose for it? Thank you

View attachment 324949

Check that large hose at the top left, that looks like it may be cracked and leaking as it is. Often the old hoses will leak and not pop off, but can be trimmed back to use the rest of the hose for a time.

Below is from my old 91 XLT. That small line on the far right of yours, above the main brake booster hose, looks out of place. See if that one will fit the nipple you have blocked off, and where the other end of that small line goes.

1991 Vacuum routing 1st gen.jpg
 






RADIOACTIVE_TOOL_SHED___

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Hi Did you get a response? My 93 just started a rough high idle and a air leak . What and where is the picture ?
Thanks Scott
The picture is on the tee where all of the vacuum lines come out of above the driver's side valve cover and no I still don't know what that hose goes too
 






ChildIdenticant

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The picture is on the tee where all of the vacuum lines come out of above the driver's side valve cover and no I still don't know what that hose goes too
Again, can't really assist you without more photos to get a sense of what components might not be hooked up correctly.
If your original question wasn't answered as clearly enough:

What does this vacuum line do?
That clear vacuum hose with the bolt in it is not a vacuum hose. It is not stock. It should not be there. It looks like it was used in place of a proper cap that belongs to block off an unused vacuum tree port.
 






RADIOACTIVE_TOOL_SHED___

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That one is probably just supposed to be capped off, but with an actual rubber cap.
Not all the ports are used, at least on mine. Unless you take a zoomed out photo, couldn't tell you what goes to what for sure. but the vacuum circuit branches are:
cruise control, auto trans, fuel pressure reg, havac , bimetal valve@ air intake, brake booster ... I think that is it.
I took some better pics

20201201_205743.jpg


20201201_205800.jpg


20201201_205724.jpg
 






ChildIdenticant

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Ok. Those pics helped a bit. Can now see that you have a different size hose ( the one zip tied to the felxible conduit) than I have seen going to your cruise control servo.
It looks like you have 6 connected hoses (can't see the back very well in any photos) which is correct, and that clear hose segment. I would first ditch that hose segment for a proper cap.
Next I would see if any of the hard hoses are connected in a stressed position ( I expect 3 of these. 1 to the FPR routes along the passenger side fuel injectors, 1 that branches to the vacuum reservoir and air cleaner and HVAC, 1 that loops around under the upper intake manifold to the egr which is mounted on the drivers).

Check that large hose at the top left,
This is good is good advice, seeing as that hose is very dirty. That hose goes to your transmission. If you have a vacuum leak (at or after the vacuum tree)so large that it is effecting idle speed it is not likely due to a partially leaking hard line, it is likely one of the larger hoses going to the trans, brake booster, or cruise control servo (listed as speed control in the linked vacuum diagram). The hard line leaks are normally noticed when accellerating.

The base of the tree is also very dirty. If the whole thing isn't sealing, that could be your trouble. But it doesn't look to me like extra treads are exposed.

just to state "Assuming this is actually a vacuum leak": You could try using smoke to find the leak/s, or test each hose segment individually with a vacuum tester ( tedious, but most reliable method to rule out individual potential causes. can break old brittle hard hose though ).

Uh.... first pic, is the hose going to you PCV (the thing directly below the tree, in the valve cover) split?

Reviewing your threads, if you just bought this in ≈october, have you checked to see if there is ratpoocake where the air filter should be? Just warrants mention as you seem to have acquired a TLC XLT.

Also, as you've not mentioned any codes yet, when you start your car, does the MIL/CEL initally illuminate like it should?
 






RADIOACTIVE_TOOL_SHED___

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Ok. Those pics helped a bit. Can now see that you have a different size hose ( the one zip tied to the felxible conduit) than I have seen going to your cruise control servo.
It looks like you have 6 connected hoses (can't see the back very well in any photos) which is correct, and that clear hose segment. I would first ditch that hose segment for a proper cap.
Next I would see if any of the hard hoses are connected in a stressed position ( I expect 3 of these. 1 to the FPR routes along the passenger side fuel injectors, 1 that branches to the vacuum reservoir and air cleaner and HVAC, 1 that loops around under the upper intake manifold to the egr which is mounted on the drivers).


This is good is good advice, seeing as that hose is very dirty. That hose goes to your transmission. If you have a vacuum leak (at or after the vacuum tree)so large that it is effecting idle speed it is not likely due to a partially leaking hard line, it is likely one of the larger hoses going to the trans, brake booster, or cruise control servo (listed as speed control in the linked vacuum diagram). The hard line leaks are normally noticed when accellerating.

The base of the tree is also very dirty. If the whole thing isn't sealing, that could be your trouble. But it doesn't look to me like extra treads are exposed.

just to state "Assuming this is actually a vacuum leak": You could try using smoke to find the leak/s, or test each hose segment individually with a vacuum tester ( tedious, but most reliable method to rule out individual potential causes. can break old brittle hard hose though ).

Uh.... first pic, is the hose going to you PCV (the thing directly below the tree, in the valve cover) split?

Reviewing your threads, if you just bought this in ≈october, have you checked to see if there is ratpoocake where the air filter should be? Just warrants mention as you seem to have acquired a TLC XLT.

Also, as you've not mentioned any codes yet, when you start your car, does the MIL/CEL initally illuminate like it should?
[/QUO there has never been a check engine light on before
 






ChildIdenticant

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there has never been a check engine light on before

The CEL should be illuminated every time you have key on, engine off . If it isn't, the bulb is missing/burnt/dislocated wiring issue etc., may have been disconnected by seller to hide problems. Don't know. But that should be sorted out first.
 






CDW6212R

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Also check the vacuum line going to the transmission, pull it off to see if there is any ATF inside it. If the modulator went bad, it would let the vacuum pull ATF through the hose.
 






RangerX

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There should be a vacuum diagram sticker on the radiator core support, is yours missing?
 












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