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4th CYLINDER SPARK PLUG HAD OIL ON TIP OF IT!

  • Thread starter Thread starter rei-04
  • Start date Start date Nov 19, 2004
R

rei-04

New Member
Sep 20, 2004
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TX
Nov 19, 2004
#1
  • Nov 19, 2004
  • #1
I pulled out my spark plugs and noticed all of them were dry, but the 4th cylinder spark plug had oil on the tip of it. What does this mean and is this bad?
 

04sleeper

Founding Member
Jun 22, 2002
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89
Dallas, TX
www.cardomain.com
Nov 19, 2004
#2
  • Nov 19, 2004
  • #2
I could be a number of things. First thing I would look to would be the valve guide seals. Also do a compression test to see if there is a difference between the other cylinders.
 
R

rei-04

New Member
Sep 20, 2004
63
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TX
Nov 19, 2004
#3
  • Nov 19, 2004
  • #3
thanks for the info. Yeah, I am about to start a compression test on it in like 5 min. I just bought this 93 5.0 abought a month ago and it has 120k miles on it. What are some good compression rates, that I should look for what is to high and what is to low? Any help would be great.
 

04sleeper

Founding Member
Jun 22, 2002
2,674
14
89
Dallas, TX
www.cardomain.com
Nov 19, 2004
#4
  • Nov 19, 2004
  • #4
rei-04 said:
thanks for the info. Yeah, I am about to start a compression test on it in like 5 min. I just bought this 93 5.0 abought a month ago and it has 120k miles on it. What are some good compression rates, that I should look for what is to high and what is to low? Any help would be great.
Click to expand...
Most cars will produce different rates. It is the variance between the cylinders that will affect the engine. I think no more than 15% difference is acceptable.

My car gave me between 130 and 140 across the board. I have 133,000 on the odometer.
 
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