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Coolant in spark plug well.

  • Thread starter Thread starter Xaiveir
  • Start date Start date Aug 18, 2009
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Xaiveir

New Member
Aug 18, 2009
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Aug 18, 2009
#1
  • Aug 18, 2009
  • #1
I want to give you as much info as i can on this, so i apologize for the novel i am about to write.

I have a 2000 GT 4.6 L. Roughly 93,000 miles on it. It has a refurb crate engine that has about 22,000 miles on it. About 2 months ago, i blew the upper intake manifold, around the thermostat housing (damn cheap plastic!). I did a temporary fix on that with an epoxy, and it drove fine. About a month after the epoxy fix i am on the freeway and i get the flashing Service Engine light come on. I limp home, and the next day i take it to Auto zone and it reads as a p306 misfire. Easy enough i peel off the boot from the spark plug, and there is coolant in spark plug well.

Knowing i blew coolant everywhere when my manifold cracked, i chalked it up to blow back, and that is just where the majority of the coolant pooled up. So i swapped out the single spark plug and it drove fine. I only swapped the one out because i was doing the manifold install the following weekend, and decided to do all the spark plugs when they are alittle more accessible.

I Did the manifold install, changed all the spark plugs the following weekend and it drove like a dream. No leaks, coolant or vacuum, no issues. Car drove better than it ever had, and it even had more power.

Fast forward 3 weeks later and i am driving down the road when i start feeling that jerking motion, or hesitation/stuttering when i accelerate. I decided to give it a day, just to see what it would do. Following day on the way to work, blinking Service engine light. I take it to Auto zone again, and surprise surprise. p306 error.

I Take it home, pull off the spark plug boot and hello! about a 1/4 of an inch of coolant in the 6th spark plug well again. I did not get a chance to pull out the plug last night. It was too late by the time i got home for it to cool down before i would run out of light.

So my question(s) is, is this just possibly left over coolant from the initial intake rupture, that got blown back into the spark plug well again? I am not leaking coolant from anywhere that i can see. My reservoir is the exact level of coolant from when i filled it up after the install.

Is this a sign of a possible head gasket issue? If so i thought the coolant would not be in the well itself. What other possible causes, or has anyone encountered a similar problem?
 

trombonedemon

Well-Known Member
Jun 25, 2009
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U.S.A, U.S.A., U.S.A.!
Aug 18, 2009
#2
  • Aug 18, 2009
  • #2
Well if it is leaking coolant, it could be a possible warped head, or like you said a head gasket issue, I imagine you changed your lower intake manifold gasket as well, doubt its a warped head though. Hey are you burning coolant anywhere? Like white smoke out the exhaust?
 
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ItsStock02

Member
Aug 18, 2008
492
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Westland, MI
Aug 18, 2009
#3
  • Aug 18, 2009
  • #3
intake manifold gasket.
 
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Xaiveir

New Member
Aug 18, 2009
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Aug 19, 2009
#4
  • Aug 19, 2009
  • #4
Thats the thing, i am NOT leaking coolant anywhere that i can tell. No white smoke out of the tailpipes. I actually used a Sharpie to mark my coolant levels at both hot and cold. Neither level has dropped to the naked eye.

So if there is coolant leaking somewhere its like a pinhole sized amount, and going right to the number 6 sparkplug.
 
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ItsStock02

Member
Aug 18, 2008
492
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Westland, MI
Aug 20, 2009
#5
  • Aug 20, 2009
  • #5
We just changed that gasket on my buddies gt and there was coolant in 3 of the spark plug wells.
 

stangsdado

Member
Aug 19, 2009
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Aug 20, 2009
#6
  • Aug 20, 2009
  • #6
Xaiveir said:
Thats the thing, i am NOT leaking coolant anywhere that i can tell. No white smoke out of the tailpipes. I actually used a Sharpie to mark my coolant levels at both hot and cold. Neither level has dropped to the naked eye.

So if there is coolant leaking somewhere its like a pinhole sized amount, and going right to the number 6 sparkplug.
Click to expand...

I can almost guarantee you that when you installed the manifold, you didn't put a pea sized amount of silicone gasket maker where the thermostat housing touches the head... Re-read your instructions and you'll notice in fine print that its recommended to use the gasket maker in addition to the lower gasket to complement the thermostat housing's weird shape.
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
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Aug 20, 2009
#7
  • Aug 20, 2009
  • #7
stangsdado said:
I can almost guarantee you that when you installed the manifold, you didn't put a pea sized amount of silicone gasket maker where the thermostat housing touches the head... Re-read your instructions and you'll notice in fine print that its recommended to use the gasket maker in addition to the lower gasket to complement the thermostat housing's weird shape.
Click to expand...
+1
 

GDawg

Founding Member
Mar 22, 2002
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Nevada
Aug 20, 2009
#8
  • Aug 20, 2009
  • #8
Kilgore Trout said:
+1
Click to expand...

+2

Not a major problem. Just fix it.
 
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