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What do these plugs say?

  • Thread starter Thread starter BlackFox5.0
  • Start date Start date May 17, 2004

BlackFox5.0

Founding Member
Aug 7, 2000
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Massachusetts
May 17, 2004
#1
  • May 17, 2004
  • #1
As the title says, whats your opinion on what my plugs are telling me?


 
S

SPEED FREAK

Founding Member
Aug 7, 2000
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Regina, SK.
May 17, 2004
#2
  • May 17, 2004
  • #2
looks like there is not a whole lot going on in that cylinder. I would check compression. But it does not look like there is any fuel on it so hmmm. possibly burning lean or not at all.
 

BlackFox5.0

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Aug 7, 2000
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May 17, 2004
#3
  • May 17, 2004
  • #3
I thought it looked lean but wanted a second opinion. I wonder if thats the reason I'm getting a bucking while crusing....I'll try adding more fuel via tweecer...

BTW the pictures are just one plug, clyinder #5
 
C

Cobra351

New Member
Mar 10, 2004
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0
May 17, 2004
#4
  • May 17, 2004
  • #4
I would say there reading about right. Go here. http://www.angelfire.com/fl4/pontiacdude428/Readplugs.html
 

BlackFox5.0

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#5
  • May 17, 2004
  • #5
According to that site, it says my plugs are reading rich by the base being so deposited with carbon....
 

Blue Thunder

15 Year Member
Mar 20, 2004
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Upstate New York.
May 17, 2004
#6
  • May 17, 2004
  • #6
I generally tune by seat of the pants, but I read this info in a car magazine.
Read plugs by the white cone and by the rainbow heat coloration on the strap. To check to see if you're running the right temperature plug, if the color wave is close to the base of the strap, you need a cooler plug, if the wave is right near the tip of the strap, you need a hotter plug.
As for fuel mixture: I look down around that porceline(sp?) cone, the further inside the plug the dark burn line gets, the leaner the condition. If the entire cone is dark, it's rich. A good mixture is when the dark line is halfway up the cone.
 

Blue Thunder

15 Year Member
Mar 20, 2004
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Upstate New York.
May 17, 2004
#7
  • May 17, 2004
  • #7
 

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Blue Thunder

15 Year Member
Mar 20, 2004
1,003
55
68
Upstate New York.
May 17, 2004
#8
  • May 17, 2004
  • #8
By the way, if you let the car idle for any length of time after a WOT blast, the plug reading will be inaccurate. You need to blast the car down the road, and then shut off the motor and coast in before removing a plug and checking it.
 
8

89lxcoupe

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Oct 6, 2001
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harlan,ky
May 18, 2004
#9
  • May 18, 2004
  • #9
they look a little lean to me like a factory plug put some more fuel to it and feel the power, they should be a light tan color no black on the porcelin looks like your total timing is a little high how much you runnin !
 

BlackFox5.0

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#10
  • May 18, 2004
  • #10
11-12* on 6psi
 

QDRHRSE

New Member
Dec 31, 2002
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Palmdale, CA
May 18, 2004
#11
  • May 18, 2004
  • #11
They look a little lean, but not as lean as a plug out of stock 5.0. Usually plugs out of stock car are almost white. I know you're not stock but you need a baseline. I would give the motor a little more fuel pressure and see what happens. I think the bucking may be an injector problem. Big injectors are finicky at low speeds. 36's right?
 

BlackFox5.0

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May 18, 2004
#12
  • May 18, 2004
  • #12
Yeah 36# injectors. I also think it could be injector related, maybe clogged up at the filter screen. On a nice day I want to take the rail out and clean every injector, and put my AFPR back on....I hope that solves this, because it sucks....
 
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