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Discussion Starter #1
Where does the "vacuum nipple"? on the throttle body connect to? It is located on the upper left corner and lower left corner on the mounting flange part. It looks more like a coolant line nipple. They are metal and bend about 90 degrees. Mine are both capped off. 1995 5.8 w/ e4od.
thanks
 

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#1 Asshole
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They are definitely coolant lines I just capped mine off to try to help lower intake temps. then I rolled the truck
 

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Discussion Starter #4
thanks for the response. I couldn't find them in any vacuum diagrams. I will leave them capped since I am in south Fla.
 

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Could you load a picture of the two capped areas? I want to try this, but want to be sure to cap the correct lines. Thanks!
 

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The top throttle body cooling tube goes down and T splices into the heater hose that ends up on the water pump and the bottom cooling tube goes over the an "octagonal shaped tree" threaded into the lower intake manifold and goes to a small tube on the tree and the engine cooling temp sensor (ECT) threads into the tree just below the small tube, the other heater hose goes to a long metal tube about 6-8 inches long threading into the side of tree.

In some cases I've seen the upper TB cooling tube hose routed straight over to and arun cross the top of the radiator and end up on a short tube just below the radiator cap, I've got that little tube blocked off.

Now your BKO is a 95 and mine is an 86 but there can't be that much difference....

Try my video library here: www.supermotors.net/17406 - T-splice, you may have to click "my flip video library" and scroll for it.

Try here: www.broncolinks.com

Good Luck ~
 

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AKA: Butthead
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They are definitely coolant lines I just capped mine off to try
to help lower intake temps.
Hmmm...
Read somewhere they thought the EGR heated the throttle body
and so it needed cooling off.

I'd test the theory but my EGR is defeated right now, so could
someone please "feel around;)" and get back with an answer?

Butthead in AZ
ps- Simple advice: Rules change so don't throw any "smog stuff"
away or burn too many bridges. Clutter in your shop or clutter in
your engine compartment... take your pick. ;)
 

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#1 Asshole
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For the egr to heat up the intake it has to be hooked up first and I kept all of the emissions stuff it just isnt hooked up mine is still clutter under the hood. but it doesnt do anything.
 

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Did you not like the answer I gave you..................?

The EGR doesn't heat up the throttle body, it's for Emissions/Gas/Return...the EGR valve is bolted to the side of the upper fuel injection plenum NEAR the TB but not directly connected, it's attached to a metal tube that threads into the lower intake manifold and has a EGR sensor attached on top with a vacuum line and electrical connector.

Check Here:
www.supermotors.net/17406 or click "my flip video library" and scroll - I've got lots of engine bay shots to view OR go here: www.broncolinks.com ....

The throttle body has upper and lower cooling tubes that are pressed in made of metal on an aluminum TB block.....they are designed to heat the fuel thru the throttle body by way of HOT COOLANT circulating thru TUBES with rubber hoses attached for cold regions etc. .....

Good Luck ~ :thumbup
 

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....

The throttle body has upper and lower cooling tubes that are pressed in made of metal on an aluminum TB block.....they are designed to heat the fuel thru the throttle body by way of HOT COOLANT circulating thru TUBES with rubber hoses attached for cold regions etc. .....

Good Luck ~ :thumbup

hmm,..... Not anywhere near 100% correct.

The fuel is at the rail to the injector, the coolant tubes on the TB is NOT going to heat any fuel. It's designed to keep the TB from freezing over in cold weather conditions.

You can disconnect these in most of the warmer states and not create any problems or wreck havoc on your engine.
 

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Satyr of the Midwest
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I wouldn't even disconnect them in a warm climate. They're to prevent freezing, yes, but to prevent them from freezing OPEN as well. Very important, IMO. :toothless

Keep in mind that snow has fallen in Florida before....
 

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If you warm the TB to keep it from freezing you warm fuel being squirted in there because they're one in the same.....and again, the EGR doesn't warm the throttle body, neither does the fuel rail ......:rofl:
 

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I wouldn't even disconnect them in a warm climate. They're to prevent freezing, yes, but to prevent them from freezing OPEN as well. Very important, IMO. :toothless

Keep in mind that snow has fallen in Florida before....
If it freezes down here and I get a stuck TB, than hell most have frozen over ;)

If you warm the TB to keep it from freezing you warm fuel being squirted in there because they're one in the same.....and again, the EGR doesn't warm the throttle body, neither does the fuel rail ......
The problem with your statement is; warm fluid doesn't pass anywhere thru the TB, it's injected a meer inch from the valves in the head , and no warm or cold fuel by any means, passes thru a TB ( throttle body ).

I ran my ricers up north with the TB coolant lines disconnect and had no problems with the under hood temps getting so cold that the TB freezes up.

fwiw

The air being drawn into the intake is cooling the intake and more so in the colder weathers, so that's why the engineers places engine coolant to warm up the TB and keep things working in the cold to extreme cold.
 

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In your case that maybe so, but my 86 Ford TB has 2 metal cooling tubes "pressed" into an aluminum block on the left side, top and bottom and if you blow on one tube end, air comes out of the other end which means the OEM 3/8 diameter tubes are stituated on the top/bottom to a 5 1/2 inch long passage inside the TB which allows for hot coolant to "circulate constanly".

IE: the top TB cooling tube and hose loops over and T splices into a heater hose below and the bottom TB cooling tube and hose is connected to a tube on an octagonal tree where the ECT is threaded, the "tree" threads in to the lower intake manifold.
All of which constantly circulate hot coolant...www.supermotors.net/17406 ~ T Splice - check my video, you may have to click "my flip video library" and scroll but it's there!


I merely saying if the temp of the coolant is say 195 degrees at the thermostat and it comes in contact/circulates thru an aluminum TB block, it's going conduct heat along with heat transferred from the engine reaching normal operating temp, ie: TB being bolted to the upper aluminum FI plenum, bolted onto the lower aluminum intake manifold....all of which conduct and transfer heat.

That being said ANYTHING coming in contact with these items at that temperature will be he affected.

Good Luck ~
 

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AKA: Butthead
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In your case that maybe so, but my 86 Ford TB has 2 metal cooling tubes
"pressed" into an aluminum block on the left side, top and bottom and if you
blow on one tube end, air comes out of the other end which means the OEM
3/8 diameter tubes are stituated on the top/bottom to a 5 1/2 inch long
passage inside the TB which allows for {...} coolant to "circulate constanly".

I merely saying if the temp of the coolant is say 195 degrees at the
thermostat and it comes in contact/circulates thru an aluminum TB block,
it's going conduct heat along with heat transferred from the engine reaching
normal operating temp, ie: TB being bolted to the upper aluminum FI plenum,
bolted onto the lower aluminum intake manifold....all of which conduct and
transfer heat.

That being said ANYTHING coming in contact with these items at that
temperature will be he affected.

Good Luck ~
Ok, cool post. :)

But. ;)

So how hot is the recirculated exhaust gas that's coming into the upper
manifold right behind the throttle body? Does it heat up anything besides
the "cold air" coming in from the -cool air induction system- Ford installed?

Remember, the TB ain't a carburetor and there's no evaporative cooling
going on at the base of it like in a carburetor. The only effect is from the
lowering of the pressure and that doesn't include a change of state like in
a refrigeration system or carburetor.

Something doesn't add up here, see it? :)

Like whoever it was that said the -coolant lines- have more to do with
-cooling- than heating because of the EGR might have it more right?

What say you? :) {shrug}

Alvin in AZ
 

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It's an oxy moran IMO, ie: cooling tubes to heat up and keep the TB from freezing in cold regions but even with a thermostat how cool can it get....? lol lol....probably not one of Fords best designs you know..

I do know that you could block off the cooling tube ends because they're a PITA but I haven't figred out if there is enough "meat" to tape in threads where the tubes are pressed in to use a bolt and sealer to make it nice and clean looking with no leaks. IIRC I read where you can re-route the ECT and connect it at the back with another harness connector to trick the computer....if you wanted to eliminate it.. but you then also have to plug the lower intake manifold hole where that went....?

The EGR valve is bolted directly onto the FI plenum very close to the TB and then it's connected to a metal flex tube which then threads into the lower intake manifold side ......so someone said they wondered if the "EGR" directly heated up the TB I guess........that's how this whole thing got started and after thinking about it I guess I realized the TB doesn't actually squirt fuel because there's no actual fuel line connection to it....though it looks like it has fuel jets inside........aaaggghhhh.

Good Luck ~ :thumbup
 

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I do know that you could block off the cooling tube ends because they're a PITA but I haven't figred out if there is enough "meat" to tape in threads where the tubes are pressed in to use a bolt and sealer to make it nice and clean looking with no leaks.

Good Luck ~ :thumbup
You don't have to get all complex with this :smilie_slap, I just snap my tubes off flush and eliminated the lines going to and from the TB that brought the coolant up to the TB.

Now that I'm on a mustang TB & EGR setup , I have no such lines to worry about, even tho some of the mustang EGR spacer did have a coolant passage in the EGR space.

FWIW, that pressed-in coolant line was a source of a very small pinhole leak that took me about 3 weeks to isolate and find in my past setup.
:cry
 

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Well I guess if you bypass the TB all together then there's no coolant being sent above, below or thru it, you could just pop in some rubber stops that fit so it looks decent, or not...lol lol....but you have to replace the one heater hose where the T slice was with a new hose obviously and just block off the lower cooling tube at the "tree" leaving just the ECT there....that works......

I cut of the old tube and taped in 3/8 threads on the "tree" because that tube was also rusting and dissolving, I threaded in a short brass 3/8 tube for the lower TB cooling tube so this way if I have any problems there, I can unscrew the brass tube, unscrew the ECT AND unscrew the octagonal tree from the lower intake without having to move the distributor out of the way....soooooo much better....

We're good! :thumbup
 
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