Read these spark plugs

Deez-67

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A few days ago my 05 started backfiring and I started to notice a bit of a ticking sound. So yesterday I went and got new plugs for it and did them last night. Sure enough one plug was loose and from the pics I bet you can tell which one it was. Anyways here is how the plugs looked. I really don't know how to read plugs so if you do and see anything please point it out to me.

Thanks for looking.





 

dysan

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Well, looks like one of them was loose letting combustion gasses get by(the non-brown one) and looks like the electrode is missing/very worn on that same plug as well as another which tells me those two cylinders were hot and/or detonating but other than that no more info can be given on the plugs. The proper way to read plugs is to see the ground strap for timing and then you need to cut the metal away and look at the color on the actual porcelain. You also need to look on the porcelain for silver specs which are also a sign of detonation.

I can't read plugs well but I do know that's what you need to look at.
 

GoneFord

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Was cylinder 1 the plug that backed out? Did you torque them to 25 ft/lbs with anti-seize?

Is your steed boosted?
 
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Deez-67

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Was cylinder 1 the plug that backed out? Did you torque them to 25 ft/lbs with anti-seize?

Is your steed boosted?

I just "guess" torque them and yes with anti-seize. This car is NA but does see a little bit of Nitrous every now and then.

They look lean to me. Scope the pistons.

That's what I was kind of thinking but like I said I don't know how to read plugs. This car has 134K of hard miles on her but I never run anything less than 100% 91 in her. I have noticed she is starting to use a little bit more oil in her older age.
 

drive_55_not

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I just "guess" torque them and yes with anti-seize. This car is NA but does see a little bit of Nitrous every now and then.



That's what I was kind of thinking but like I said I don't know how to read plugs. This car has 134K of hard miles on her but I never run anything less than 100% 91 in her. I have noticed she is starting to use a little bit more oil in her older age.


Looks you've got some quite a bit pinging going on, 91 the best gas you have in OK?


.
 

VTXFrank

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In the first picture, the top right and lowest left plugs show signs of detonation for sure since the center electrodes are all but gone.

If you're running a tune, you need to have one degree of timing removed at WOT. If you are only running a tune for Nitrous, then you need to get a better ON DYNO tune done for it.

I also see signs of spark blowout and/or overly rich condition on five plugs which is very likely from the nitrous tune or lack thereof. If you aren't running a tune for nitrous, you need to stop spraying until you get one. If you are running a tune, you need to get a better one.....like a true Dyno Tune.

Some plugs show a lean condition while others show a slightly rich condition. Which is what makes me doubt you have a dedicated Nitrous tune.


More info needed.

After you replace those plugs, the ONLY way to get a TRUE read on your plugs is by doing a third or fourth gear WOT pull to redline, IMMEDIATELY shut off the engine and coast to the side of the road. Pull the plugs RIGHT there before restarting the motor. Take your pictures.
 
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DiMora

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Yeah...top right and bottom left electrodes are gone. Looks lean.

Top right was clearly not firing like the others.

As stated above, you may need better gas, less timing, a richer tune, or a combo of the above. And some new plugs!
 

phattyfat

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IMO you can't really read those plugs properly other than saying one was not seated, you're burning some oil and 2 cylinders got crazy hot due to the melted electrode. But that could have only been on one pass on the spray and you never noticed it. Peppering on the electrode may indicate detonation but you stated that you're burning oil so that causes false positive detonation readings. The only way to read that parameter is to put in some fresh plugs and do what VTXFRANK suggested and read it with a magnifying glass. Now you'll have to do that both NA and on the sauce to determine when it's happening. I suspect on the sauce and you should get a n2o tune to load in when spraying. What size jettings are you using and are those stock heat range plugs? At 11-12 dollars a piece reading plugs properly can get expensive.
 

Deez-67

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Thank you guys for all the input.

I'm running mail order tunes. I have a 91 daily a 93 all motor and a 93 nitrous.

Sounds like I need to get this girl dyno tuned.
 
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