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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Inspection of old spark plugs, quick?

  • Thread starter Thread starter TheGrayt1
  • Start date Start date Apr 27, 2008

TheGrayt1

Member
Apr 16, 2008
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6
Plano, Texas
Apr 27, 2008
#1
  • Apr 27, 2008
  • #1
I changed my spark plugs yesterday and after looking at all the COP's and plugs they all looked good. The COP's were clean, and all the plugs tips were a fairly consistent light golden brown with no major deposits. The only one that had anything on it was the #7 plug, drivers side second from the back firewall. It did not have anything on the tip but had a little oil it looks like or dirt on the threads of the plug. Is this anything to worry about? The car is running great and never missed on that cylinder.
 
D

darkside03gt

Member
Feb 19, 2007
851
8
18
Sacramento CA
Apr 27, 2008
#2
  • Apr 27, 2008
  • #2
I wouldnt worry about the dirt. now the oil on the other hand. How much was on it and what color was it? if your really concerned about it do a compression and leakdown test. it will give you a indication of how the rings are doing in that cylinder.
 

TheGrayt1

Member
Apr 16, 2008
44
0
6
Plano, Texas
Apr 27, 2008
#3
  • Apr 27, 2008
  • #3
Yea it is pretty dark and looks sort of like oil, but it is only on the threads of the plug. It is not a ton just a light coating.
 
D

Dragstr05

New Member
Dec 21, 2004
643
1
0
Stafford VA
Apr 27, 2008
#4
  • Apr 27, 2008
  • #4
I wouldnt worry about it.
 

BurningRubber

10 Year Member
Dec 6, 2004
1,865
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58
Apr 27, 2008
#5
  • Apr 27, 2008
  • #5
If your valve cover gaskets are old and leaky a little oil can seep down in the plug gallies.

If thats not the case then a little oil is either getting my the rings or the valve seals.
 

TheGrayt1

Member
Apr 16, 2008
44
0
6
Plano, Texas
Apr 27, 2008
#6
  • Apr 27, 2008
  • #6
These plugs were very old, should I just drive a little bit around and recheck this cylinder and see if there is any oil on the threads? What is weird is there is no oil on the electrode, but there is oil on the threads.
 

BurningRubber

10 Year Member
Dec 6, 2004
1,865
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Apr 27, 2008
#7
  • Apr 27, 2008
  • #7
Thats what id do.

A couple of mine were like that, no big sweat though.
 

TheGrayt1

Member
Apr 16, 2008
44
0
6
Plano, Texas
Apr 27, 2008
#8
  • Apr 27, 2008
  • #8
BurningRubber said:
Thats what id do.

A couple of mine were like that, no big sweat though.
Click to expand...

A few of your plugs had some oil on the threads too? I just bought the car and it runs great and am fanatical about taking care of my stuff. The car runs great and fires right up and does not struggle to start like it had low compression. I was just wondering if anyone else had experienced oil on the threads of their old plugs. The plugs were pretty old from what I can tell. I can email someone pics of what they looked like. The files are too large for this forum.

Do these cars use oil in between changes? I just changed the oil for the first time last week and the level stays constant but it has not been that long. Thanks in advance.
 

BurningRubber

10 Year Member
Dec 6, 2004
1,865
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58
Apr 27, 2008
#9
  • Apr 27, 2008
  • #9
I beleive 1 or 2 of mine had a small amount of oil on the threads.

I do not know if its an internal problem or the valve cover gaskets. They seem to seep JUST enough to collect dirt and buildup around that area. I did find oil collected near my coil packs in a few spots, so that may be the source.

If you upload the pics on photobucket.com you can re-size them.

Also, my car uses about 1 quart of oil between changes. 2 cylinders are also down around 30psi from the others, so thats probaly my issue. If there are no issues, then it should use very minimal to no noticable loss of oil. Always keep a check on it to be safe though.
 

40th GT

New Member
Apr 7, 2004
916
0
0
Lawrenceville, GA
Apr 28, 2008
#10
  • Apr 28, 2008
  • #10
BurningRubber said:
I beleive 1 or 2 of mine had a small amount of oil on the threads.

I do not know if its an internal problem or the valve cover gaskets. They seem to seep JUST enough to collect dirt and buildup around that area. I did find oil collected near my coil packs in a few spots, so that may be the source.

If you upload the pics on photobucket.com you can re-size them.

Also, my car uses about 1 quart of oil between changes. 2 cylinders are also down around 30psi from the others, so thats probaly my issue. If there are no issues, then it should use very minimal to no noticable loss of oil. Always keep a check on it to be safe though.
Click to expand...
And how many miles do you have?
 
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