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throttle body coolant?

  • Thread starter Thread starter deftsound
  • Start date Start date Aug 16, 2005

deftsound

Please ask me how much my supercharger cost
Apr 6, 2004
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Texas City TX
Aug 16, 2005
#1
  • Aug 16, 2005
  • #1
yesterday while replacing the throttle body gasket i noticed there was a coolant line going to it and that coolant had been leaking in between the gasket on the throttle body and the intake plenum. My question is, can someone please explain to me why there is a coolant line running to the throttle body?
 

88 Fox GT

Active Member
Nov 18, 2002
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Aug 16, 2005
#2
  • Aug 16, 2005
  • #2
It makes the throttle body cooler. Just ask people who have bypassed it. I've seem some say that it actually gets hotter when bypassed.
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
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59
windsor, Canada
Aug 16, 2005
#3
  • Aug 16, 2005
  • #3
Those lines in and out of the TB are used to affect EGR temps..If you had coolant leaking then def get the gasket replaced and tighten her up. I would change the oil also..I don't like the idea of coolant getting into the engine..especially anywhere near the oil.
 

CManT1914

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Feb 5, 2004
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Killeen, Texas
Aug 16, 2005
#4
  • Aug 16, 2005
  • #4
Is this a fox-only setup? Don't LT1's or LS1's have a setup like this where coolant flows to the throttle body?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Aug 16, 2005
#5
  • Aug 16, 2005
  • #5
It has been done on many motors. The EGR gasses can be 600-700*F++ so the 200*F coolant helps cool the housing that your cool incoming air is passing through.

Derek's advice is quite good.

Good luck.
 
8

8950HO

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Mar 31, 2005
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Aug 16, 2005
#6
  • Aug 16, 2005
  • #6
The only time to by-pass coolant to the EGR spacer is when the EGR system is eliminated,eg,blocking off the EGR ports in the cylinder heads.

Otherwise the coolant is there to cool the EGR spacer that carries the hot exhaust gasses from the cylinder heads through the intake manifold.

If the EGR is functional,don`t disconnect the coolant lines .
 

sgarlic

Founding Member
Apr 21, 2001
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Aug 16, 2005
#7
  • Aug 16, 2005
  • #7
I've heard that as well to not disconnect them.. my buddy has a '95 Bronco with a 5.0, he capped off both the lines, hasn't had an issue.. guess it's a preference thing. Mine are intact.. barely.
 

vristang

15 Year Member
Mar 31, 2005
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Seattle
Aug 16, 2005
#8
  • Aug 16, 2005
  • #8
I am a little confused, but I guess that is normal.

If the EGR gasses run to the intake air via the lower and then upper manifold, then why did Ford not cool the entire intake? It seems pretty meaningless to cool the TB when the exhaust gasses have already dumped all that heat into the lower and upper intake.

Also, I have heard some debate on this. Some feel the coolant lines were there to bring heat to the TB for quicker warmups. Did the stock coolant line routing bring hot coolant that had just left the block to the TB? I haven't seen stock in a few years so I don't remember.

I just wanted to toss this out to see what all of you really smart guys think.

Also, I ran my Cobra manifold on the 302 for a couple of years w/o the coolant running to the EGR. Didn't seem to have any heating/cooling problems.

jason
 

LX302

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Aug 17, 2005
#9
  • Aug 17, 2005
  • #9
Ford installed the coolant lines to keep the throttle body from possibly freezing in low temps, but like vristang said, the Cobra intake eliminated it.
So to answer your question, you can keep it or cap it, it won't effect on how your car runs.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Aug 17, 2005
#10
  • Aug 17, 2005
  • #10
LX302 said:
Ford installed the coolant lines to keep the throttle body from possibly freezing in low temps, but like vristang said, the Cobra intake eliminated it.
So to answer your question, you can keep it or cap it, it won't effect on how your car runs.
Click to expand...
If one wanted to de-ice the TB, the lines are not going to the correct component. Furthermore, a heat riser off the headers would be more effective in this capacity.
 

90mustangGT

I felt sorry for girls because
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Jan 15, 2002
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Aug 17, 2005
#11
  • Aug 17, 2005
  • #11
Those lines are to both cool the EGR gasses and prevent freezing of the TB. It heats the whole intake, I removed mine and the intake did run cooler.
 

vristang

15 Year Member
Mar 31, 2005
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Aug 17, 2005
#12
  • Aug 17, 2005
  • #12
I have to respectfully disagree with the freezing TB theory as well.

I don't see how any part of the engine could freeze when it was running, regardless of ambient temps. When the motor is not running though the coolant lines wouldn't do any good anyway.

Without knowing what Ford was intending with these coolant lines, I hesitate to give a recommendation as to whether or not they can/should be plugged.
 

88 Fox GT

Active Member
Nov 18, 2002
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Aug 17, 2005
#13
  • Aug 17, 2005
  • #13
HISSIN50 said:
If one wanted to de-ice the TB, the lines are not going to the correct component. Furthermore, a heat riser off the headers would be more effective in this capacity.
Click to expand...
Exactly, because they aren't going to be hot until the engine is hot. And when the engine is hot, it's doing fine heating the TB.
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
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Mill Creek, WA
Aug 17, 2005
#14
  • Aug 17, 2005
  • #14
I don't know what they're for. I don't buy the cooling theory due to the Cobra intake, and I don't buy the heating theory due to the coolant warm up issues.

I think maybe they were an idea for something else and just got left behind somehow.
 
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