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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

What Does This Spark Plug Tell You

  • Thread starter Thread starter BigE85
  • Start date Start date May 15, 2017

BigE85

Member
Feb 3, 2017
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13
Kansas
May 15, 2017
#1
  • May 15, 2017
  • #1
Hey guys i cant figure out why these spark plugs look like this. What is the color telling me. These spark plugs are ngk iridium ur45ix
 

a91what

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Apr 6, 2011
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May 15, 2017
#2
  • May 15, 2017
  • #2
You are burning oil, depending on plug age it could be minor or pcv related.
The Orangebrown insulator says you are burning rich at idle and possible leaded fuel.... does this motor see race fuel? may want to go up a heat range on the plug.
A lot of deposits on the electrode ground says go up a heat range, I can't read the anelment mark.
You a tad too rich says the outer ring.

Stop wasting money on iridium plugs, copper plugs work very well and are my preference in nitrous and boosted applications.
 

BigE85

Member
Feb 3, 2017
28
4
13
Kansas
May 15, 2017
#3
  • May 15, 2017
  • #3
Yeah did put a little bit of race fuel in. what do you suggest i do. change the plugs to copper and see why im running rich were do i go from here plugs are new only have maybe 200 miles on them.
 

a91what

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#4
  • May 15, 2017
  • #4
What kind of engine build is this details please.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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May 15, 2017
#5
  • May 15, 2017
  • #5
No NGK plugs.... They work best in imports ( for whatever reason ). Our cars run best with regular copper plugs...Autolite or Motorcraft.
 
Reactions: deathb4dismount

BigE85

Member
Feb 3, 2017
28
4
13
Kansas
May 15, 2017
#6
  • May 15, 2017
  • #6
Yeah thats what i thought. But i got a good price on them. And i seen other people use them. So i thought it would not cause a problem. But i still dont understand what the problem is. Never seen a plug look like this all 8 look the same. Could a ignition coil be the problem. It has a new distriburator and tfi module new wires
 

Saberstang

Active Member
May 2, 2017
130
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28
Atlanta, GA
May 16, 2017
#7
  • May 16, 2017
  • #7
Your plug says you are burning oil to some degree. Motorcraft or Autolite spark plugs are the only spark plugs I would use on our cars. NGK and Bosch spark plugs would be the worst choice.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,226
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Massachusetts
May 16, 2017
#8
  • May 16, 2017
  • #8
BigE85 said:
But i still dont understand what the problem is. Never seen a plug look like this all 8 look the same. Could a ignition coil be the problem. It has a new distriburator and tfi module new wires
Click to expand...

What;s the entire engine combo? Why are you putting in race fuel?
 

BigE85

Member
Feb 3, 2017
28
4
13
Kansas
May 20, 2017
#9
  • May 20, 2017
  • #9
Im sorry i never got back with you my phone broke. im sorry i did not run race fuel it was a lucas octane booster. And im stock right now. But have heads,intake,cai,maf,cam,roller rockers,throttle body,new fuel pump,24ibl injectors,headers,msd idgntion,bama chip,but was trying to get this problem fix before i added all this.change the plugs to copper motorcraft plugs and made a world of diffrence. but still bogs down i think i have a fuel problem. Thanks for the help.
 
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